diff --git a/BizHawk.Emulation/BizHawk.Emulation.csproj b/BizHawk.Emulation/BizHawk.Emulation.csproj
index 611e8db33d..ade0cb89de 100644
--- a/BizHawk.Emulation/BizHawk.Emulation.csproj
+++ b/BizHawk.Emulation/BizHawk.Emulation.csproj
@@ -357,6 +357,7 @@
     <Compile Include="Consoles\Sega\Genesis\Cart\RomHeader.cs" />
     <Compile Include="Consoles\Sega\Genesis\Cart\SaveRAM.cs" />
     <Compile Include="Consoles\Sega\Genesis\Input.cs" />
+    <Compile Include="Consoles\Sega\Saturn\FilePiping.cs" />
     <Compile Include="Consoles\Sega\Saturn\LibYabause.cs" />
     <Compile Include="Consoles\Sega\Saturn\Yabause.cs" />
     <Compile Include="Consoles\Sega\SMS\MemoryMap.CodeMasters.cs" />
diff --git a/BizHawk.Emulation/Consoles/Sega/Saturn/FilePiping.cs b/BizHawk.Emulation/Consoles/Sega/Saturn/FilePiping.cs
new file mode 100644
index 0000000000..ca7c297752
--- /dev/null
+++ b/BizHawk.Emulation/Consoles/Sega/Saturn/FilePiping.cs
@@ -0,0 +1,80 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.IO;
+using System.IO.Pipes;
+using System.Threading;
+
+namespace BizHawk.Emulation.Consoles.Sega.Saturn
+{
+	/// <summary>
+	/// helpers for moving files across named pipes
+	/// </summary>
+	public class FilePiping
+	{
+		public void Offer(byte[] data)
+		{
+			MemoryStream ms = new MemoryStream(data, false);
+			Offer(ms);
+		}
+
+		string PipeName;
+		Thread thr;
+		Exception e;
+
+		public string GetPipeName()
+		{
+			return PipeName;
+		}
+
+		public string GetPipeNameNative()
+		{
+			return @"\\.\pipe\" + PipeName;
+		}
+
+		public FilePiping()
+		{
+			PipeName = "BizHawk-" + Guid.NewGuid().ToString();
+		}
+
+		public void Offer(Stream s)
+		{
+			if (thr != null)
+				throw new Exception("Can only serve one thing at a time!");
+			if (e != null)
+				throw new Exception("Previous attempt failed!", e);
+			if (!s.CanRead)
+				throw new ArgumentException("Stream must be readable!");
+
+			thr = new Thread(delegate()
+				{
+					try
+					{
+						using (var srv = new NamedPipeServerStream(PipeName, PipeDirection.Out))
+						{
+							srv.WaitForConnection();
+							s.CopyTo(srv);
+							srv.WaitForPipeDrain();
+						}
+					}
+					catch (Exception ee)// might want to do something about this...
+					{
+						e = ee;
+					}
+				});
+			thr.Start();
+		}
+
+		public Exception GetResults()
+		{
+			if (thr == null)
+				throw new Exception("No pending!");
+			thr.Join();
+			thr = null;
+			Exception ret = e;
+			e = null;
+			return ret;
+		}
+	}
+}
diff --git a/BizHawk.Emulation/Consoles/Sega/Saturn/LibYabause.cs b/BizHawk.Emulation/Consoles/Sega/Saturn/LibYabause.cs
index 1eeac89f85..30e2aa2f3e 100644
--- a/BizHawk.Emulation/Consoles/Sega/Saturn/LibYabause.cs
+++ b/BizHawk.Emulation/Consoles/Sega/Saturn/LibYabause.cs
@@ -83,9 +83,10 @@ namespace BizHawk.Emulation.Consoles.Sega.Saturn
 		/// 
 		/// </summary>
 		/// <param name="intf">cd interface.  struct need not persist after call, but the function pointers better</param>
+		/// <param name="biosfn">path to bios, pass null to use built in bios emulation</param>
 		/// <returns></returns>
 		[DllImport("libyabause.dll", CallingConvention = CallingConvention.Cdecl)]
-		public static extern bool libyabause_init(ref CDInterface intf);
+		public static extern bool libyabause_init(ref CDInterface intf, string biosfn);
 
 		public struct CDInterface
 		{
diff --git a/BizHawk.Emulation/Consoles/Sega/Saturn/Yabause.cs b/BizHawk.Emulation/Consoles/Sega/Saturn/Yabause.cs
index b5465bd53d..be795792ef 100644
--- a/BizHawk.Emulation/Consoles/Sega/Saturn/Yabause.cs
+++ b/BizHawk.Emulation/Consoles/Sega/Saturn/Yabause.cs
@@ -33,16 +33,16 @@ namespace BizHawk.Emulation.Consoles.Sega.Saturn
 		LibYabause.CDInterface.ReadSectorFAD ReadSectorFADH;
 		LibYabause.CDInterface.ReadAheadFAD ReadAheadFADH;
 
-		public Yabause(CoreComm CoreComm, DiscSystem.Disc CD)
+		public Yabause(CoreComm CoreComm, DiscSystem.Disc CD, byte[] bios)
 		{
 			CoreComm.RomStatusDetails = "Yeh";
 			this.CoreComm = CoreComm;
 			this.CD = CD;
 			ResetFrameCounter();
-			Init();
+			Init(bios);
 		}
 
-		void Init()
+		void Init(byte[] bios)
 		{
 			if (AttachedCore != null)
 			{
@@ -60,9 +60,17 @@ namespace BizHawk.Emulation.Consoles.Sega.Saturn
 			CDInt.ReadSectorFADFunc = ReadSectorFADH = new LibYabause.CDInterface.ReadSectorFAD(CD_ReadSectorFAD);
 			CDInt.ReadAheadFADFunc = ReadAheadFADH = new LibYabause.CDInterface.ReadAheadFAD(CD_ReadAheadFAD);
 
-			if (!LibYabause.libyabause_init(ref CDInt))
+			var fp = new FilePiping();
+			string BiosPipe = fp.GetPipeNameNative();
+			fp.Offer(bios);
+
+			if (!LibYabause.libyabause_init(ref CDInt, BiosPipe))
 				throw new Exception("libyabause_init() failed!");
 
+			var e = fp.GetResults();
+			if (e != null)
+				throw e;
+
 			LibYabause.libyabause_setvidbuff(VideoHandle.AddrOfPinnedObject());
 			LibYabause.libyabause_setsndbuff(SoundHandle.AddrOfPinnedObject());
 			AttachedCore = this;
diff --git a/BizHawk.MultiClient/Config.cs b/BizHawk.MultiClient/Config.cs
index e732f3cb6d..48c9cc1708 100644
--- a/BizHawk.MultiClient/Config.cs
+++ b/BizHawk.MultiClient/Config.cs
@@ -256,6 +256,7 @@ namespace BizHawk.MultiClient
 		public string FilenameA78PALBios = "7800PALBIOS.bin";
 		public string FilenameA78HSCBios = "7800highscore.bin";
 		public string FilenameINTVEROM = "erom.bin";
+		public string FilenameSaturnBios = "Sega Saturn BIOS v1.01 (JAP).bin";
 
 		public string FFMpegPath = "%exe%/dll/ffmpeg.exe";
 
diff --git a/BizHawk.MultiClient/MainForm.cs b/BizHawk.MultiClient/MainForm.cs
index efa481cc3a..37b1d0a5bc 100644
--- a/BizHawk.MultiClient/MainForm.cs
+++ b/BizHawk.MultiClient/MainForm.cs
@@ -2082,8 +2082,16 @@ namespace BizHawk.MultiClient
 						switch (game.System)
 						{
 							case "SAT":
-								var saturn = new Emulation.Consoles.Sega.Saturn.Yabause(nextComm, disc);
-								nextEmulator = saturn;
+								{
+									string biosPath = PathManager.StandardFirmwareName(Global.Config.FilenameSaturnBios);
+									if (!File.Exists(biosPath))
+									{
+										MessageBox.Show("Saturn BIOS not found.  Please check firmware configurations.");
+										return false;
+									}
+									var saturn = new Emulation.Consoles.Sega.Saturn.Yabause(nextComm, disc, File.ReadAllBytes(biosPath));
+									nextEmulator = saturn;
+								}
 								break;
 
 							case "PSX":
diff --git a/BizHawk.MultiClient/output/dll/libyabause.dll b/BizHawk.MultiClient/output/dll/libyabause.dll
index db22f4b26c..e437a48e49 100644
Binary files a/BizHawk.MultiClient/output/dll/libyabause.dll and b/BizHawk.MultiClient/output/dll/libyabause.dll differ
diff --git a/yabause/src/libyabause/yui.cpp b/yabause/src/libyabause/yui.cpp
index c147e1fbc8..91cf54a18e 100644
--- a/yabause/src/libyabause/yui.cpp
+++ b/yabause/src/libyabause/yui.cpp
@@ -201,7 +201,7 @@ extern "C" __declspec(dllexport) void libyabause_setpads(u8 p11, u8 p12, u8 p21,
 	ctrl2->padbits[1] = p22;
 }
 
-extern "C" __declspec(dllexport) int libyabause_init(CDInterface *_CD)
+extern "C" __declspec(dllexport) int libyabause_init(CDInterface *_CD, const char *biosfn)
 {
 	FECD.DeInit = _CD->DeInit;
 	FECD.GetStatus = _CD->GetStatus;
@@ -227,7 +227,7 @@ extern "C" __declspec(dllexport) int libyabause_init(CDInterface *_CD)
 	yinit.m68kcoretype = M68KCORE_C68K;
 	yinit.cartpath = CART_NONE;
 	yinit.regionid = REGION_AUTODETECT;
-	yinit.biospath = NULL;
+	yinit.biospath = biosfn;
 	yinit.cdpath = "Saturnus"; //NULL;
 	yinit.buppath = NULL;
 	yinit.mpegpath = NULL;
diff --git a/yabause/src/memory.h b/yabause/src/memory.h
index 2de4cbdc47..7cab523ea7 100644
--- a/yabause/src/memory.h
+++ b/yabause/src/memory.h
@@ -194,7 +194,7 @@ static INLINE void T3WriteLong(T3Memory * mem, u32 addr, u32 val)
 static INLINE int T123Load(void * mem, u32 size, int type, const char *filename)
 {
    FILE *fp;
-   u32 filesize, filesizecheck;
+   u32 filesizecheck;
    u8 *buffer;
    u32 i;
 
@@ -205,41 +205,47 @@ static INLINE int T123Load(void * mem, u32 size, int type, const char *filename)
       return -1;
 
    // Calculate file size
-   fseek(fp, 0, SEEK_END);
-   filesize = ftell(fp);
-   fseek(fp, 0, SEEK_SET);
+   //fseek(fp, 0, SEEK_END);
+   //filesize = ftell(fp);
+   //fseek(fp, 0, SEEK_SET);
 
-   if (filesize > size)
-      return -1;
+   //if (filesize > size)
+   //   return -1;
 
-   if ((buffer = (u8 *)malloc(filesize)) == NULL)
+   if ((buffer = (u8 *)malloc(size)) == NULL)
    {
       fclose(fp);
       return -1;
    }
 
-   filesizecheck = (u32)fread((void *)buffer, 1, filesize, fp);
-   fclose(fp);
+   filesizecheck = (u32)fread((void *)buffer, 1, size, fp);
+   // make sure there are no bytes left in the file
+   if (filesizecheck != size || fgetc(fp) != EOF)
+   {
+      free(buffer);
+      fclose(fp);
+      return -1;
+   }
 
-   if (filesizecheck != filesize) return -1;
+   fclose(fp);
 
    switch (type)
    {
       case 1:
       {
-         for (i = 0; i < filesize; i++)
+         for (i = 0; i < size; i++)
             T1WriteByte((u8 *) mem, i, buffer[i]);
          break;
       }
       case 2:
       {
-         for (i = 0; i < filesize; i++)
+         for (i = 0; i < size; i++)
             T2WriteByte((u8 *) mem, i, buffer[i]);
          break;
       }
       case 3:
       {
-         for (i = 0; i < filesize; i++)
+         for (i = 0; i < size; i++)
             T3WriteByte((T3Memory *) mem, i, buffer[i]);
          break;
       }