diff --git a/src/BizHawk.Client.Common/tools/RamSearchEngine/RamSearchEngine.cs b/src/BizHawk.Client.Common/tools/RamSearchEngine/RamSearchEngine.cs
index 2169959453..b46eb47c93 100644
--- a/src/BizHawk.Client.Common/tools/RamSearchEngine/RamSearchEngine.cs
+++ b/src/BizHawk.Client.Common/tools/RamSearchEngine/RamSearchEngine.cs
@@ -89,10 +89,12 @@ namespace BizHawk.Client.Common.RamSearchEngine
 				_watchList[index].Previous,
 				_settings.IsDetailed() ? _watchList[index].ChangeCount : 0);
 
-		public int DoSearch()
+		public int DoSearch(bool updatePrevious)
 		{
 			int before = _watchList.Length;
 
+			Update(updatePrevious);
+
 			using (Domain.EnterExit())
 			{
 				_watchList = _compareTo switch
@@ -169,12 +171,12 @@ namespace BizHawk.Client.Common.RamSearchEngine
 		/// </remarks>
 		public int? DifferentBy { get; set; }
 
-		public void Update()
+		public void Update(bool updatePrevious)
 		{
 			using var @lock = _settings.Domain.EnterExit();
 			foreach (var watch in _watchList)
 			{
-				watch.Update(_settings.PreviousType, _settings.Domain, _settings.BigEndian);
+				watch.Update(updatePrevious ? _settings.PreviousType : PreviousType.Original, _settings.Domain, _settings.BigEndian);
 			}
 		}
 
@@ -182,20 +184,13 @@ namespace BizHawk.Client.Common.RamSearchEngine
 
 		public void SetEndian(bool bigEndian) => _settings.BigEndian = bigEndian;
 
-		/// <exception cref="InvalidOperationException"><see cref="Mode"/> is <see cref="SearchMode.Fast"/> and <paramref name="type"/> is <see cref="PreviousType.LastFrame"/></exception>
-		public void SetPreviousType(PreviousType type)
-		{
-			if (_settings.IsFastMode() && type == PreviousType.LastFrame)
-			{
-				throw new InvalidOperationException();
-			}
+		public void SetPreviousType(PreviousType type) => _settings.PreviousType = type;
 
-			_settings.PreviousType = type;
-		}
+		public void SetMode(SearchMode mode) => _settings.Mode = mode;
 
 		public void SetPreviousToCurrent()
 		{
-			Array.ForEach(_watchList, w => w.SetPreviousToCurrent(_settings.Domain, _settings.BigEndian));
+			Array.ForEach(_watchList, static w => w.SetPreviousToCurrent());
 		}
 
 		public void ClearChangeCounts()
@@ -450,7 +445,7 @@ namespace BizHawk.Client.Common.RamSearchEngine
 
 		private IEnumerable<IMiniWatch> CompareChanges(IEnumerable<IMiniWatch> watchList)
 		{
-			if (CompareValue is not long compareValue) throw new InvalidCastException(); //TODO typo for IOE?
+			if (CompareValue is not long compareValue) throw new InvalidOperationException();
 			switch (Operator)
 			{
 				default:
diff --git a/src/BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs b/src/BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs
index fcf05523e5..369e4828d9 100644
--- a/src/BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs
+++ b/src/BizHawk.Client.EmuHawk/tools/Watch/RamSearch.cs
@@ -270,8 +270,6 @@ namespace BizHawk.Client.EmuHawk
 		{
 			if (_searches.Count > 0)
 			{
-				_searches.Update();
-
 				if (_autoSearch)
 				{
 					if (InputPollableCore != null && Settings.AutoSearchTakeLagFramesIntoAccount && InputPollableCore.IsLagFrame)
@@ -280,21 +278,24 @@ namespace BizHawk.Client.EmuHawk
 					}
 					else
 					{
-						DoSearch();
+						DoSearch(true);
 					}
 				}
+				else if (_settings.IsDetailed())
+				{
+					_searches.Update(true);
+				}
 
 				_forcePreviewClear = false;
 				WatchListView.RowCount = _searches.Count;
 			}
 		}
 
+		// TODO: this seems to be missing some logic from FrameUpdate that probably should exist here
 		private void MinimalUpdate()
 		{
 			if (_searches.Count > 0)
 			{
-				_searches.Update();
-
 				if (_autoSearch)
 				{
 					DoSearch();
@@ -521,14 +522,14 @@ namespace BizHawk.Client.EmuHawk
 			}
 		}
 
-		public void DoSearch()
+		public void DoSearch(bool updatePrevious = false)
 		{
 			_searches.CompareValue = CompareToValue;
 			_searches.DifferentBy = DifferentByValue;
 			_searches.Operator = Operator;
 			_searches.CompareTo = Compare;
 
-			var removed = _searches.DoSearch();
+			var removed = _searches.DoSearch(updatePrevious);
 			UpdateList();
 			SetRemovedMessage(removed);
 			ToggleSearchDependentToolBarItems();
@@ -587,7 +588,6 @@ namespace BizHawk.Client.EmuHawk
 				&& _settings.IsDetailed())
 			{
 				_settings.Mode = SearchMode.Fast;
-				SetReboot(true);
 				MessageLabel.Text = "Large domain, switching to fast mode";
 			}
 		}
@@ -753,6 +753,7 @@ namespace BizHawk.Client.EmuHawk
 		private void SetToDetailedMode()
 		{
 			_settings.Mode = SearchMode.Detailed;
+			_searches.SetMode(SearchMode.Detailed);
 			NumberOfChangesRadio.Enabled = true;
 			NumberOfChangesBox.Enabled = true;
 			DifferenceRadio.Enabled = true;
@@ -763,7 +764,6 @@ namespace BizHawk.Client.EmuHawk
 			ChangesMenuItem.Checked = true;
 
 			ColumnToggleCallback();
-			SetReboot(true);
 		}
 
 		private ToolStripMenuItem ChangesMenuItem
@@ -782,6 +782,7 @@ namespace BizHawk.Client.EmuHawk
 		private void SetToFastMode()
 		{
 			_settings.Mode = SearchMode.Fast;
+			_searches.SetMode(SearchMode.Fast);
 
 			if (_settings.PreviousType == PreviousType.LastFrame || _settings.PreviousType == PreviousType.LastChange)
 			{
@@ -802,7 +803,6 @@ namespace BizHawk.Client.EmuHawk
 			ChangesMenuItem.Checked = false;
 
 			ColumnToggleCallback();
-			SetReboot(true);
 		}
 
 		private void RemoveAddresses()