Nope, I think it's a good idea now.

Revert "This reverts commit c878c85daeaaf0cae3e28f24bc1a8b511293d7b6."
This reverts commit 1d1f2a18c6.

BizHawk.Client.Common/Api/Classes/EmuApi.cs

@@ -195,7 +195,7 @@ namespace BizHawk.Client.Common
 			_ => (object) null
 		};
 
-		public bool PutSettings(object settings) => Emulator switch
+		public PutSettingsDirtyBits PutSettings(object settings) => Emulator switch
 		{
 			GPGX gpgx => gpgx.PutSettings((GPGX.GPGXSettings) settings),
 			LibsnesCore snes => snes.PutSettings((LibsnesCore.SnesSettings) settings),
@@ -204,7 +204,7 @@ namespace BizHawk.Client.Common
 			QuickNES quickNes => quickNes.PutSettings((QuickNES.QuickNESSettings) settings),
 			SMS sms => sms.PutSettings((SMS.SmsSettings) settings),
 			WonderSwan ws => ws.PutSettings((WonderSwan.Settings) settings),
-			_ => false
+			_ => PutSettingsDirtyBits.None
 		};
 
 		public void SetRenderPlanes(params bool[] args)

BizHawk.Client.Common/Api/Interfaces/IEmu.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using BizHawk.Emulation.Common;
 
 namespace BizHawk.Client.Common
 {
@@ -26,7 +27,7 @@ namespace BizHawk.Client.Common
 		string GetDisplayType();
 		string GetBoardName();
 		object GetSettings();
-		bool PutSettings(object settings);
+		PutSettingsDirtyBits PutSettings(object settings);
 		void SetRenderPlanes(params bool[] args);
 	}
 }

BizHawk.Client.EmuHawk/MainForm.cs

@@ -2305,10 +2305,11 @@ namespace BizHawk.Client.EmuHawk
 		public void PutCoreSettings(object o)
 		{
 			var settable = new SettingsAdapter(Emulator);
-			if (settable.HasSettings && settable.PutSettings(o))
+			if (!settable.HasSettings)
-			{
+				return;
+			var dirty = settable.PutSettings(o);
+			if(dirty.HasFlag(PutSettingsDirtyBits.RebootCore))
 				FlagNeedsReboot();
-			}
 		}
 
 		// TODO: Get/Put settings/sync settings methods could become a service we instantiate and use and pass to other forms
@@ -2322,9 +2323,13 @@ namespace BizHawk.Client.EmuHawk
 			{
 				AddOnScreenMessage("Attempt to change sync-relevant settings while recording BLOCKED.");
 			}
-			else if (settable.HasSyncSettings && settable.PutSyncSettings(o))
+			else
 			{
-				FlagNeedsReboot();
+				if (!settable.HasSyncSettings)
+					return;
+				var dirty = settable.PutSyncSettings(o);
+				if(dirty.HasFlag(PutSettingsDirtyBits.RebootCore))
+					FlagNeedsReboot();
 			}
 		}
 

BizHawk.Emulation.Common/Interfaces/Services/ISettable.cs

@@ -41,7 +41,7 @@ namespace BizHawk.Emulation.Common
 		/// </summary>
 		/// <param name="o">an object of the same type as the return for GetSettings</param>
 		/// <returns>true if a core reboot will be required to make the changes effective</returns>
-		bool PutSettings(TSettings o);
+		PutSettingsDirtyBits PutSettings(TSettings o);
 
 		/// <summary>
 		/// changes the movie-sync relevant settings.  THIS SHOULD NEVER BE CALLED WHILE RECORDING
@@ -49,7 +49,19 @@ namespace BizHawk.Emulation.Common
 		/// </summary>
 		/// <param name="o">an object of the same type as the return for GetSyncSettings</param>
 		/// <returns>true if a core reboot will be required to make the changes effective</returns>
-		bool PutSyncSettings(TSync o);
+		PutSettingsDirtyBits PutSyncSettings(TSync o);
+	}
+
+	//note: this is a bit of a frail API. If a frontend wants a new flag, cores won't know to yea or nay it
+	//this could be solved by adding a KnownSettingsDirtyBits on the settings interface
+	//or, in a pinch, the same thing could be done with THESE flags, so that the interface doesn't 
+	//change but newly-aware cores can simply manifest that they know about more bits, in the same variable they return the bits in
+	[Flags]
+	public enum PutSettingsDirtyBits
+	{
+		None = 0,
+		RebootCore = 1,
+		ScreenLayoutChanged = 2,
 	}
 
 	/// <summary>
@@ -126,7 +138,7 @@ namespace BizHawk.Emulation.Common
 		}
 
 		/// <exception cref="InvalidOperationException">does not have non-sync settings</exception>
-		public bool PutSettings(object o)
+		public PutSettingsDirtyBits PutSettings(object o)
 		{
 			if (!HasSettings)
 			{
@@ -134,11 +146,11 @@ namespace BizHawk.Emulation.Common
 			}
 
 			_tmp1[0] = o;
-			return (bool)_puts.Invoke(_emu, _tmp1);
+			return (PutSettingsDirtyBits)_puts.Invoke(_emu, _tmp1);
 		}
 
 		/// <exception cref="InvalidOperationException">does not have sync settings</exception>
-		public bool PutSyncSettings(object o)
+		public PutSettingsDirtyBits PutSyncSettings(object o)
 		{
 			if (!HasSyncSettings)
 			{
@@ -146,7 +158,7 @@ namespace BizHawk.Emulation.Common
 			}
 
 			_tmp1[0] = o;
-			return (bool)_putss.Invoke(_emu, _tmp1);
+			return (PutSettingsDirtyBits)_putss.Invoke(_emu, _tmp1);
 		}
 	}
 }

BizHawk.Emulation.Cores/Arcades/MAME/MAME.cs

@@ -257,18 +257,18 @@ namespace BizHawk.Emulation.Cores.Arcades.MAME
 		#region ISettable
 
 		public object GetSettings() => null;
-		public bool PutSettings(object o) => false;
+		public PutSettingsDirtyBits PutSettings(object o) => PutSettingsDirtyBits.None;
 
 		public SyncSettings GetSyncSettings()
 		{
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			bool ret = SyncSettings.NeedsReboot(o, _syncSettings);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public class SyncSettings

BizHawk.Emulation.Cores/Calculator/TI83.ISettable.cs

@@ -11,10 +11,10 @@ namespace BizHawk.Emulation.Cores.Calculators
 			return _settings.Clone();
 		}
 
-		public bool PutSettings(TI83Settings o)
+		public PutSettingsDirtyBits PutSettings(TI83Settings o)
 		{
 			_settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
 		public object GetSyncSettings()
@@ -22,9 +22,9 @@ namespace BizHawk.Emulation.Cores.Calculators
 			return null;
 		}
 
-		public bool PutSyncSettings(object o)
+		public PutSettingsDirtyBits PutSyncSettings(object o)
 		{
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
 		public class TI83Settings

BizHawk.Emulation.Cores/Computers/AmstradCPC/AmstradCPC.ISettable.cs

@@ -25,7 +25,7 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 			return SyncSettings.Clone();
 		}
 
-		public bool PutSettings(AmstradCPCSettings o)
+		public PutSettingsDirtyBits PutSettings(AmstradCPCSettings o)
 		{
 
 			// restore user settings to devices
@@ -42,14 +42,14 @@ namespace BizHawk.Emulation.Cores.Computers.AmstradCPC
 
 			Settings = o;
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(AmstradCPCSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(AmstradCPCSyncSettings o)
 		{
 			bool ret = AmstradCPCSyncSettings.NeedsReboot(SyncSettings, o);
 			SyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public class AmstradCPCSettings

BizHawk.Emulation.Cores/Computers/AppleII/AppleII.ISettable.cs

@@ -20,16 +20,16 @@ namespace BizHawk.Emulation.Cores.Computers.AppleII
 
 		public object GetSyncSettings() => null;
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			_settings = o;
 			_machine.Video.IsMonochrome = _settings.Monochrome;
 
 			SetCallbacks();
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(object o) => false;
+		public PutSettingsDirtyBits PutSyncSettings(object o) => PutSettingsDirtyBits.None;
 	}
 }

BizHawk.Emulation.Cores/Computers/Commodore64/C64.ISettable.cs

@@ -16,16 +16,16 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64
 			return SyncSettings.Clone();
 		}
 
-		public bool PutSettings(C64Settings o)
+		public PutSettingsDirtyBits PutSettings(C64Settings o)
 		{
 			Settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(C64SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(C64SyncSettings o)
 		{
 			SyncSettings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
 		internal C64Settings Settings { get; private set; }

BizHawk.Emulation.Cores/Computers/MSX/MSX.ISettable.cs

@@ -16,18 +16,18 @@ namespace BizHawk.Emulation.Cores.Computers.MSX
 			return SyncSettings.Clone();
 		}
 
-		public bool PutSettings(MSXSettings o)
+		public PutSettingsDirtyBits PutSettings(MSXSettings o)
 		{
 			bool ret = MSXSettings.RebootNeeded(Settings, o);
 			Settings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(MSXSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(MSXSyncSettings o)
 		{
 			bool ret = MSXSyncSettings.RebootNeeded(SyncSettings, o);
 			SyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		internal MSXSettings Settings { get; private set; }

BizHawk.Emulation.Cores/Computers/SinclairSpectrum/ZXSpectrum.ISettable.cs

@@ -20,7 +20,7 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 
 		public ZXSpectrumSyncSettings GetSyncSettings() => SyncSettings.Clone();
 
-		public bool PutSettings(ZXSpectrumSettings o)
+		public PutSettingsDirtyBits PutSettings(ZXSpectrumSettings o)
 		{
 			// restore user settings to devices
 			if (_machine?.AYDevice != null)
@@ -39,14 +39,14 @@ namespace BizHawk.Emulation.Cores.Computers.SinclairSpectrum
 
 			Settings = o;
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(ZXSpectrumSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(ZXSpectrumSyncSettings o)
 		{
 			bool ret = ZXSpectrumSyncSettings.NeedsReboot(SyncSettings, o);
 			SyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public class ZXSpectrumSettings

BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.ISettable.cs

@@ -21,7 +21,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
 			return SyncSettings.Clone();
 		}
 
-		public bool PutSettings(A2600Settings o)
+		public PutSettingsDirtyBits PutSettings(A2600Settings o)
 		{
 			if (Settings == null || Settings.SECAMColors != o.SECAMColors)
 			{
@@ -29,14 +29,14 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
 			}
 
 			Settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(A2600SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(A2600SyncSettings o)
 		{
 			bool ret = A2600SyncSettings.NeedsReboot(SyncSettings, o);
 			SyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		internal A2600Settings Settings { get; private set; }

BizHawk.Emulation.Cores/Consoles/Atari/A7800Hawk/A7800Hawk.ISettable.cs

@@ -18,17 +18,17 @@ namespace BizHawk.Emulation.Cores.Atari.A7800Hawk
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(A7800Settings o)
+		public PutSettingsDirtyBits PutSettings(A7800Settings o)
 		{
 			_settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(A7800SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(A7800SyncSettings o)
 		{
 			bool ret = A7800SyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private A7800Settings _settings = new A7800Settings();

BizHawk.Emulation.Cores/Consoles/Coleco/ColecoVision.ISettable.cs

@@ -18,18 +18,18 @@ namespace BizHawk.Emulation.Cores.ColecoVision
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(ColecoSettings o)
+		public PutSettingsDirtyBits PutSettings(ColecoSettings o)
 		{
 			_settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(ColecoSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(ColecoSyncSettings o)
 		{
 			bool ret = o.SkipBiosIntro != _syncSettings.SkipBiosIntro;
 			ret |= ColecoSyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public class ColecoSettings

BizHawk.Emulation.Cores/Consoles/Fairchild/ChannelF/ChannelF.ISettable.cs

@@ -19,17 +19,17 @@ namespace BizHawk.Emulation.Cores.Consoles.ChannelF
 			return SyncSettings.Clone();
 		}
 
-		public bool PutSettings(ChannelFSettings o)
+		public PutSettingsDirtyBits PutSettings(ChannelFSettings o)
 		{
 			Settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(ChannelFSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(ChannelFSyncSettings o)
 		{
 			bool ret = ChannelFSyncSettings.NeedsReboot(SyncSettings, o);
 			SyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public class ChannelFSettings

BizHawk.Emulation.Cores/Consoles/GCE/Vectrex/VectrexHawk.ISettable.cs

@@ -19,17 +19,17 @@ namespace BizHawk.Emulation.Cores.Consoles.Vectrex
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(VectrexSettings o)
+		public PutSettingsDirtyBits PutSettings(VectrexSettings o)
 		{
 			_settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(VectrexSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(VectrexSyncSettings o)
 		{
 			bool ret = VectrexSyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private VectrexSettings _settings = new VectrexSettings();

BizHawk.Emulation.Cores/Consoles/Intellivision/Intellivision.ISettable.cs

@@ -18,17 +18,17 @@ namespace BizHawk.Emulation.Cores.Intellivision
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(IntvSettings o)
+		public PutSettingsDirtyBits PutSettings(IntvSettings o)
 		{
 			_settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(IntvSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(IntvSyncSettings o)
 		{
 			bool ret = IntvSyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private IntvSettings _settings = new IntvSettings();

BizHawk.Emulation.Cores/Consoles/Magnavox/Odyssey2/O2Hawk.ISettable.cs

@@ -16,17 +16,17 @@ namespace BizHawk.Emulation.Cores.Consoles.O2Hawk
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(O2Settings o)
+		public PutSettingsDirtyBits PutSettings(O2Settings o)
 		{
 			_settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(O2SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(O2SyncSettings o)
 		{
 			bool ret = O2SyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public O2Settings _settings = new O2Settings();

BizHawk.Emulation.Cores/Consoles/NEC/PCFX/Tst.cs

@@ -330,19 +330,19 @@ namespace BizHawk.Emulation.Cores.Consoles.NEC.PCFX
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			var ret = Settings.NeedsReboot(_settings, o);
 			_settings = o;
 			SetLayerSettings();
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			var ret = SyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private void SetNativeSettingsBeforeInit()

BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/MGBAHawk.ISettable.cs

@@ -15,7 +15,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 			return _settings.Clone();
 		}
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			LibmGBA.Layers mask = 0;
 			if (o.DisplayBG0) mask |= LibmGBA.Layers.BG0;
@@ -51,7 +51,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 			LibmGBA.BizSetPalette(Core, palette);
 
 			_settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
 		private Settings _settings;
@@ -139,11 +139,11 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			bool ret = SyncSettings.NeedsReboot(o, _syncSettings);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private SyncSettings _syncSettings;

BizHawk.Emulation.Cores/Consoles/Nintendo/GBA/VBANext.ISettings.cs

@@ -18,16 +18,16 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBA
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(object o)
+		public PutSettingsDirtyBits PutSettings(object o)
 		{
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			bool ret = SyncSettings.NeedsReboot(o, _syncSettings);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private SyncSettings _syncSettings;

BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/GBHawk.ISettable.cs

@@ -20,17 +20,17 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(GBSettings o)
+		public PutSettingsDirtyBits PutSettings(GBSettings o)
 		{
 			_settings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(GBSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(GBSyncSettings o)
 		{
 			bool ret = GBSyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private GBSettings _settings = new GBSettings();

BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink/GBHawkLink.ISettable.cs

@@ -14,17 +14,17 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawkLink
 
 		public GBLinkSyncSettings GetSyncSettings() => linkSyncSettings.Clone();
 
-		public bool PutSettings(GBLinkSettings o)
+		public PutSettingsDirtyBits PutSettings(GBLinkSettings o)
 		{
 			linkSettings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(GBLinkSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(GBLinkSyncSettings o)
 		{
 			bool ret = GBLinkSyncSettings.NeedsReboot(linkSyncSettings, o);
 			linkSyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private GBLinkSettings linkSettings = new GBLinkSettings();

BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink3x/GBHawkLink3x.ISettable.cs

@@ -14,17 +14,17 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawkLink3x
 
 		public GBLink3xSyncSettings GetSyncSettings() => Link3xSyncSettings.Clone();
 
-		public bool PutSettings(GBLink3xSettings o)
+		public PutSettingsDirtyBits PutSettings(GBLink3xSettings o)
 		{
 			Link3xSettings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(GBLink3xSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(GBLink3xSyncSettings o)
 		{
 			bool ret = GBLink3xSyncSettings.NeedsReboot(Link3xSyncSettings, o);
 			Link3xSyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private GBLink3xSettings Link3xSettings = new GBLink3xSettings();

BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawkLink4x/GBHawkLink4x.ISettable.cs

@@ -14,17 +14,17 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawkLink4x
 
 		public GBLink4xSyncSettings GetSyncSettings() => Link4xSyncSettings.Clone();
 
-		public bool PutSettings(GBLink4xSettings o)
+		public PutSettingsDirtyBits PutSettings(GBLink4xSettings o)
 		{
 			Link4xSettings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(GBLink4xSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(GBLink4xSyncSettings o)
 		{
 			bool ret = GBLink4xSyncSettings.NeedsReboot(Link4xSyncSettings, o);
 			Link4xSyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private GBLink4xSettings Link4xSettings = new GBLink4xSettings();

BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Gambatte.ISettable.cs

@@ -14,7 +14,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 			return _settings.Clone();
 		}
 
-		public bool PutSettings(GambatteSettings o)
+		public PutSettingsDirtyBits PutSettings(GambatteSettings o)
 		{
 			_settings = o;
 			if (IsCGBMode())
@@ -26,7 +26,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 				ChangeDMGColors(_settings.GBPalette);
 			}
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
 		public GambatteSyncSettings GetSyncSettings()
@@ -34,11 +34,11 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSyncSettings(GambatteSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(GambatteSyncSettings o)
 		{
 			bool ret = GambatteSyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private GambatteSettings _settings;

BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/GambatteLink.ISettable.cs

@@ -21,14 +21,14 @@ namespace BizHawk.Emulation.Cores.Nintendo.Gameboy
 			);
 		}
 
-		public bool PutSettings(GambatteLinkSettings o)
+		public PutSettingsDirtyBits PutSettings(GambatteLinkSettings o)
 		{
-			return L.PutSettings(o.L) || R.PutSettings(o.R);
+			return (PutSettingsDirtyBits)((int)L.PutSettings(o.L) | (int)R.PutSettings(o.R));
 		}
 
-		public bool PutSyncSettings(GambatteLinkSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(GambatteLinkSyncSettings o)
 		{
-			return L.PutSyncSettings(o.L) || R.PutSyncSettings(o.R);
+			return (PutSettingsDirtyBits)((int)L.PutSyncSettings(o.L) | (int)R.PutSyncSettings(o.R));
 		}
 
 		public class GambatteLinkSettings

BizHawk.Emulation.Cores/Consoles/Nintendo/Gameboy/Sameboy.cs

@@ -245,18 +245,18 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.Gameboy
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			var ret = Settings.NeedsReboot(_settings, o);
 			_settings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			var ret = SyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		#endregion

BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.ISettable.cs

@@ -14,17 +14,17 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(N64Settings o)
+		public PutSettingsDirtyBits PutSettings(N64Settings o)
 		{
 			_settings = o;
-			return true;
+			return PutSettingsDirtyBits.RebootCore;
 		}
 
-		public bool PutSyncSettings(N64SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(N64SyncSettings o)
 		{
 			_syncSettings = o;
 			SetControllerButtons();
-			return true;
+			return PutSettingsDirtyBits.RebootCore;
 		}
 
 		private void SetControllerButtons()

BizHawk.Emulation.Cores/Consoles/Nintendo/NDS/MelonDS_Settable.cs

@@ -30,14 +30,14 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 			return ret;
 		}
 
-		public bool PutSettings(MelonSettings o)
+		public PutSettingsDirtyBits PutSettings(MelonSettings o)
 		{
 			_settings = o ?? new MelonSettings();
 			SetScaleFactor(_settings.ScaleFactor);
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(MelonSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(MelonSyncSettings o)
 		{
 			if (o == null)
 			{
@@ -54,7 +54,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.NDS
 			SetTimeAtBoot(o.TimeAtBoot);
 
 			// At present, no sync settings can be modified without requiring a reboot.
-			return true;
+			return PutSettingsDirtyBits.RebootCore;
 		}
 
 		[DllImport(dllPath)]

BizHawk.Emulation.Cores/Consoles/Nintendo/NES/NES.ISettable.cs

@@ -12,7 +12,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 
 		public NESSyncSettings GetSyncSettings() => SyncSettings.Clone();
 
-		public bool PutSettings(NESSettings o)
+		public PutSettingsDirtyBits PutSettings(NESSettings o)
 		{
 			Settings = o;
 			if (Settings.ClipLeftAndRight)
@@ -30,14 +30,14 @@ namespace BizHawk.Emulation.Cores.Nintendo.NES
 
 			apu.m_vol = Settings.APU_vol;
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(NESSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(NESSyncSettings o)
 		{
 			bool ret = NESSyncSettings.NeedsReboot(SyncSettings, o);
 			SyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		internal NESSettings Settings = new NESSettings();

BizHawk.Emulation.Cores/Consoles/Nintendo/QuickNES/QuickNES.ISettable.cs

@@ -21,21 +21,21 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.QuickNES
 			return _syncSettingsNext.Clone();
 		}
 
-		public bool PutSettings(QuickNESSettings o)
+		public PutSettingsDirtyBits PutSettings(QuickNESSettings o)
 		{
 			_settings = o;
 			QN.qn_set_sprite_limit(Context, _settings.NumSprites);
 			RecalculateCrops();
 			CalculatePalette();
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(QuickNESSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(QuickNESSyncSettings o)
 		{
 			bool ret = QuickNESSyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettingsNext = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private QuickNESSettings _settings;

BizHawk.Emulation.Cores/Consoles/Nintendo/SNES/LibsnesCore.ISettable.cs

@@ -14,7 +14,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(SnesSettings o)
+		public PutSettingsDirtyBits PutSettings(SnesSettings o)
 		{
 			bool refreshNeeded = o.Palette != _settings.Palette;
 			_settings = o;
@@ -23,17 +23,17 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES
 				RefreshPalette();
 			}
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SnesSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SnesSyncSettings o)
 		{
 			bool ret = o.LeftPort != _syncSettings.LeftPort
 				|| o.RightPort != _syncSettings.RightPort
 				|| o.LimitAnalogChangeSensitivity != _syncSettings.LimitAnalogChangeSensitivity;
 
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private SnesSettings _settings;

BizHawk.Emulation.Cores/Consoles/Nintendo/SNES9X/Snes9x.cs

@@ -308,7 +308,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES9X
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			_settings = o;
 			int s = 0;
@@ -334,14 +334,14 @@ namespace BizHawk.Emulation.Cores.Nintendo.SNES9X
 			if (o.ShowSprites3) l |= 2048;
 			_core.biz_set_layers(l);
 
-			return false; // no reboot needed
+			return PutSettingsDirtyBits.None; // no reboot needed
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			var ret = SyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public class Settings

BizHawk.Emulation.Cores/Consoles/Nintendo/SubGBHawk/SubGBHawk.cs

@@ -58,7 +58,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SubGBHawk
 
 		public GBHawk.GBHawk.GBSettings GetSettings() => _GBCore.GetSettings();
 		public GBHawk.GBHawk.GBSyncSettings GetSyncSettings() => _GBCore.GetSyncSettings();
-		public bool PutSettings(GBHawk.GBHawk.GBSettings o) => _GBCore.PutSettings(o);
+		public PutSettingsDirtyBits PutSettings(GBHawk.GBHawk.GBSettings o) => _GBCore.PutSettings(o);
-		public bool PutSyncSettings(GBHawk.GBHawk.GBSyncSettings o) => _GBCore.PutSyncSettings(o);
+		public PutSettingsDirtyBits PutSyncSettings(GBHawk.GBHawk.GBSyncSettings o) => _GBCore.PutSyncSettings(o);
 	}
 }

BizHawk.Emulation.Cores/Consoles/Nintendo/SubNESHawk/SubNESHawk.cs

@@ -84,7 +84,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.SubNESHawk
 
 		public NES.NES.NESSettings GetSettings() => _nesCore.GetSettings();
 		public NES.NES.NESSyncSettings GetSyncSettings() => _nesCore.GetSyncSettings();
-		public bool PutSettings(NES.NES.NESSettings o) => _nesCore.PutSettings(o);
+		public PutSettingsDirtyBits PutSettings(NES.NES.NESSettings o) => _nesCore.PutSettings(o);
-		public bool PutSyncSettings(NES.NES.NESSyncSettings o) => _nesCore.PutSyncSettings(o);
+		public PutSettingsDirtyBits PutSyncSettings(NES.NES.NESSyncSettings o) => _nesCore.PutSyncSettings(o);
 	}
 }

BizHawk.Emulation.Cores/Consoles/Nintendo/VB/VirtualBoyee.cs

@@ -234,18 +234,18 @@ namespace BizHawk.Emulation.Cores.Consoles.Nintendo.VB
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			var ret = Settings.NeedsReboot(_settings, o);
 			_settings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			var ret = SyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		#endregion

BizHawk.Emulation.Cores/Consoles/PC Engine/PCEngine.ISettable.cs

@@ -17,7 +17,7 @@ namespace BizHawk.Emulation.Cores.PCEngine
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(PCESettings o)
+		public PutSettingsDirtyBits PutSettings(PCESettings o)
 		{
 			bool ret;
 			if (o.ArcadeCardRewindHack != Settings.ArcadeCardRewindHack
@@ -32,14 +32,14 @@ namespace BizHawk.Emulation.Cores.PCEngine
 
 			Settings = o;
 
-			return ret;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(PCESyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(PCESyncSettings o)
 		{
 			bool ret = PCESyncSettings.NeedsReboot(o, _syncSettings);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public PCESettings Settings;

BizHawk.Emulation.Cores/Consoles/SNK/NeoGeoPort.cs

@@ -166,16 +166,16 @@ namespace BizHawk.Emulation.Cores.Consoles.SNK
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(object o)
+		public PutSettingsDirtyBits PutSettings(object o)
 		{
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			var ret = SyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		#endregion

BizHawk.Emulation.Cores/Consoles/Sega/GGHawkLink/GGHawkLink.ISettable.cs

@@ -16,17 +16,17 @@ namespace BizHawk.Emulation.Cores.Sega.GGHawkLink
 			return linkSyncSettings.Clone();
 		}
 
-		public bool PutSettings(GGLinkSettings o)
+		public PutSettingsDirtyBits PutSettings(GGLinkSettings o)
 		{
 			linkSettings = o;
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(GGLinkSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(GGLinkSyncSettings o)
 		{
 			bool ret = GGLinkSyncSettings.NeedsReboot(linkSyncSettings, o);
 			linkSyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private GGLinkSettings linkSettings = new GGLinkSettings();

BizHawk.Emulation.Cores/Consoles/Sega/PicoDrive/PicoDrive.cs

@@ -229,16 +229,16 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.PicoDrive
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(object o)
+		public PutSettingsDirtyBits PutSettings(object o)
 		{
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			var ret = SyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		#endregion

BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.ISettable.cs

@@ -9,18 +9,18 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 
 		public SmsSyncSettings GetSyncSettings() => SyncSettings.Clone();
 
-		public bool PutSettings(SmsSettings o)
+		public PutSettingsDirtyBits PutSettings(SmsSettings o)
 		{
 			bool ret = SmsSettings.RebootNeeded(Settings, o);
 			Settings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SmsSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SmsSyncSettings o)
 		{
 			bool ret = SmsSyncSettings.RebootNeeded(SyncSettings, o);
 			SyncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		internal SmsSettings Settings { get; private set; }

BizHawk.Emulation.Cores/Consoles/Sega/Saturn/Saturnus.cs

@@ -439,7 +439,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.Saturn
 			return _settings.Clone();
 		}
 
-		public bool PutSettings(Settings s)
+		public PutSettingsDirtyBits PutSettings(Settings s)
 		{
 			var ret = Settings.NeedsReboot(_settings, s);
 			_settings = s;
@@ -449,7 +449,7 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.Saturn
 			//(the correct aspect ratio is no longer an option for other reasons)
 			//_core.SetVideoParameters(s.CorrectAspectRatio, s.HBlend, s.HOverscan, sls, sle);
 
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		public SyncSettings GetSyncSettings()
@@ -457,11 +457,11 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.Saturn
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSyncSettings(SyncSettings s)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings s)
 		{
 			var ret = SyncSettings.NeedsReboot(_syncSettings, s);
 			_syncSettings = s;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private void SetVideoParameters()

BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.ISettable.cs

@@ -21,19 +21,19 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 			return _syncSettings.Clone();
 		}
 
-		public bool PutSettings(GPGXSettings o)
+		public PutSettingsDirtyBits PutSettings(GPGXSettings o)
 		{
 			bool ret = GPGXSettings.NeedsReboot(_settings, o);
 			_settings = o;
 			Core.gpgx_set_draw_mask(_settings.GetDrawMask());
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(GPGXSyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(GPGXSyncSettings o)
 		{
 			bool ret = GPGXSyncSettings.NeedsReboot(_syncSettings, o);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		private class UintToHexConverter : TypeConverter

BizHawk.Emulation.Cores/Consoles/Sony/PSX/Octoshock.cs

@@ -1271,17 +1271,17 @@ namespace BizHawk.Emulation.Cores.Sony.PSX
 			return _SyncSettings.Clone();
 		}
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			_Settings.Validate();
 			_Settings = o;
 
 			//TODO - store settings into core? or we can just keep doing it before frameadvance
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			//currently LEC and pad settings changes both require reboot
 			bool reboot = true;
@@ -1293,7 +1293,7 @@ namespace BizHawk.Emulation.Cores.Sony.PSX
 			_SyncSettings = o;
 
 
-			return reboot;
+			return reboot ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 		#endregion

BizHawk.Emulation.Cores/Consoles/WonderSwan/WonderSwan.ISettable.cs

@@ -158,19 +158,19 @@ namespace BizHawk.Emulation.Cores.WonderSwan
 
 		public SyncSettings GetSyncSettings() => _syncSettings.Clone();
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			_settings = o;
 			var native = _settings.GetNativeSettings();
 			BizSwan.bizswan_putsettings(Core, ref native);
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			bool ret = SyncSettings.NeedsReboot(o, _syncSettings);
 			_syncSettings = o;
-			return ret;
+			return ret ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 
 	}

BizHawk.Emulation.Cores/Libretro/LibretroCoreSettings.cs

@@ -1,5 +1,6 @@
 using Newtonsoft.Json;
 using BizHawk.Common;
+using BizHawk.Emulation.Common;
 
 namespace BizHawk.Emulation.Cores.Libretro
 {
@@ -49,17 +50,17 @@ namespace BizHawk.Emulation.Cores.Libretro
 			return _SyncSettings.Clone();
 		}
 
-		public bool PutSettings(Settings o)
+		public PutSettingsDirtyBits PutSettings(Settings o)
 		{
 			_Settings.Validate();
 			_Settings = o;
 
 			//TODO - store settings into core? or we can just keep doing it before frameadvance
 
-			return false;
+			return PutSettingsDirtyBits.None;
 		}
 
-		public bool PutSyncSettings(SyncSettings o)
+		public PutSettingsDirtyBits PutSyncSettings(SyncSettings o)
 		{
 			bool reboot = false;
 
@@ -68,7 +69,7 @@ namespace BizHawk.Emulation.Cores.Libretro
 
 			_SyncSettings = o;
 
-			return reboot;
+			return reboot ? PutSettingsDirtyBits.RebootCore : PutSettingsDirtyBits.None;
 		}
 	}