diff --git a/desmume/src/windows/main.cpp b/desmume/src/windows/main.cpp
index 9aa24add8..702d47904 100644
--- a/desmume/src/windows/main.cpp
+++ b/desmume/src/windows/main.cpp
@@ -1463,8 +1463,6 @@ static struct MainLoopData
 	u64 lastticks;
 	u64 curticks;
 	u64 diffticks;
-	u32 framecount;
-	u64 onesecondticks;
 	u64 fpsticks;
 	HWND hwnd;
 	int fps;
@@ -1618,40 +1616,26 @@ static void StepRunLoop_Throttle(bool allowSleep = true, int forceFrameSkip = -1
 		if (mainLoopData.framestoskip < 1)
 			mainLoopData.framestoskip += ffSkipRate;
 	}
-	else if((autoframeskipenab || FrameLimit) && allowSleep)
+	else if((/*autoframeskipenab ||*/ FrameLimit) && allowSleep)
 	{
-		while(SpeedThrottle())
-		{
-		}
+		SpeedThrottle();
 	}
 
 	if (autoframeskipenab)
 	{
-		mainLoopData.framecount++;
-
-		if (mainLoopData.framecount > 60)
+		if(!frameAdvance && !continuousframeAdvancing)
 		{
-			mainLoopData.framecount = 1;
-			mainLoopData.onesecondticks = 0;
+			AutoFrameSkip_NextFrame();
+			if (mainLoopData.framestoskip < 1)
+				mainLoopData.framestoskip += AutoFrameSkip_GetSkipAmount(0,skipRate);
 		}
-
-		QueryPerformanceCounter((LARGE_INTEGER *)&mainLoopData.curticks);
-		mainLoopData.diffticks = mainLoopData.curticks - mainLoopData.lastticks;
-
-		if(ThrottleIsBehind() && (mainLoopData.framesskipped < ffSkipRate))
-		{
-			mainLoopData.skipnextframe = 1;
-			mainLoopData.framestoskip = 1;
-		}
-
-		mainLoopData.onesecondticks += mainLoopData.diffticks;
-		mainLoopData.lastticks = mainLoopData.curticks;
 	}
 	else
 	{
 		if (mainLoopData.framestoskip < 1)
 			mainLoopData.framestoskip += skipRate;
 	}
+
 	if (frameAdvance && allowSleep)
 	{
 		frameAdvance = false;
@@ -2424,17 +2408,20 @@ int _main()
 
 	GetPrivateProfileString("Video", "FrameSkip", "0", text, 80, IniName);
 
-	if (strcmp(text, "AUTO") == 0)
+	if(!strncmp(text, "AUTO", 4))
 	{
 		autoframeskipenab=1;
-		frameskiprate=0;
-		MainWindow->checkMenu(IDC_FRAMESKIPAUTO, true);
+		if(!text[4])
+			frameskiprate=9;
+		else
+			frameskiprate=atoi(text+4);
+		if(frameskiprate < 1)
+			frameskiprate = 9;
 	}
 	else
 	{
 		autoframeskipenab=0;
 		frameskiprate=atoi(text);
-		MainWindow->checkMenu(frameskiprate + IDC_FRAMESKIP0, true);
 	}
 
 	if (KeyInDelayMSec == 0) {
@@ -3573,8 +3560,15 @@ LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM
 			MainWindow->checkMenu(IDC_FRAMELIMIT, FrameLimit);
 			
 			//Frame Skip
-			MainWindow->checkMenu(IDC_FRAMESKIPAUTO, ((autoframeskipenab)));
-
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO1, (autoframeskipenab && frameskiprate==1) );
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO2, (autoframeskipenab && frameskiprate==2) );
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO3, (autoframeskipenab && frameskiprate==3) );
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO4, (autoframeskipenab && frameskiprate==4) );
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO5, (autoframeskipenab && frameskiprate==5) );
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO6, (autoframeskipenab && frameskiprate==6) );
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO7, (autoframeskipenab && frameskiprate==7) );
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO8, (autoframeskipenab && frameskiprate==8) );
+			MainWindow->checkMenu(IDC_FRAMESKIPAUTO9, (autoframeskipenab && frameskiprate==9) );
 			MainWindow->checkMenu(IDC_FRAMESKIP0, (!autoframeskipenab && frameskiprate==0) );
 			MainWindow->checkMenu(IDC_FRAMESKIP1, (!autoframeskipenab && frameskiprate==1) );
 			MainWindow->checkMenu(IDC_FRAMESKIP2, (!autoframeskipenab && frameskiprate==2) );
@@ -4740,7 +4734,23 @@ LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM
 				if(tpaused) NDS_UnPause();
 			}
 			return 0;
-		case IDC_FRAMESKIPAUTO:
+		case IDC_FRAMESKIPAUTO1:
+		case IDC_FRAMESKIPAUTO2:
+		case IDC_FRAMESKIPAUTO3:
+		case IDC_FRAMESKIPAUTO4:
+		case IDC_FRAMESKIPAUTO5:
+		case IDC_FRAMESKIPAUTO6:
+		case IDC_FRAMESKIPAUTO7:
+		case IDC_FRAMESKIPAUTO8:
+		case IDC_FRAMESKIPAUTO9:
+			{
+				char text[80];
+				autoframeskipenab = 1;
+				frameskiprate = LOWORD(wParam) - (IDC_FRAMESKIPAUTO1 - 1);
+				sprintf(text, "AUTO%d", frameskiprate);
+				WritePrivateProfileString("Video", "FrameSkip", text, IniName);
+			}
+			return 0;
 		case IDC_FRAMESKIP0:
 		case IDC_FRAMESKIP1:
 		case IDC_FRAMESKIP2:
@@ -4752,19 +4762,11 @@ LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM
 		case IDC_FRAMESKIP8:
 		case IDC_FRAMESKIP9:
 			{
-				if(LOWORD(wParam) == IDC_FRAMESKIPAUTO)
-				{
-					autoframeskipenab = 1;
-					WritePrivateProfileString("Video", "FrameSkip", "AUTO", IniName);
-				}
-				else
-				{
-					char text[80];
-					autoframeskipenab = 0;
-					frameskiprate = LOWORD(wParam) - IDC_FRAMESKIP0;
-					sprintf(text, "%d", frameskiprate);
-					WritePrivateProfileString("Video", "FrameSkip", text, IniName);
-				}
+				char text[80];
+				autoframeskipenab = 0;
+				frameskiprate = LOWORD(wParam) - IDC_FRAMESKIP0;
+				sprintf(text, "%d", frameskiprate);
+				WritePrivateProfileString("Video", "FrameSkip", text, IniName);
 			}
 			return 0;
 		case IDC_NEW_LUA_SCRIPT:
diff --git a/desmume/src/windows/resource.h b/desmume/src/windows/resource.h
index 371dc761c..3bdbd995e 100644
--- a/desmume/src/windows/resource.h
+++ b/desmume/src/windows/resource.h
@@ -77,7 +77,6 @@
 #define IDC_SAVETYPE4                   185
 #define IDC_SAVETYPE5                   186
 #define IDC_SAVETYPE6                   187
-#define IDC_FRAMESKIPAUTO               190
 #define IDC_FRAMESKIP0                  191
 #define IDC_FRAMESKIP1                  192
 #define IDC_FRAMESKIP2                  193
@@ -97,6 +96,15 @@
 #define IDC_LANGDANISH                  212
 #define IDM_MGPU                        213
 #define IDM_SGPU                        214
+#define IDC_FRAMESKIPAUTO1              221
+#define IDC_FRAMESKIPAUTO2              222
+#define IDC_FRAMESKIPAUTO3              223
+#define IDC_FRAMESKIPAUTO4              224
+#define IDC_FRAMESKIPAUTO5              225
+#define IDC_FRAMESKIPAUTO6              226
+#define IDC_FRAMESKIPAUTO7              227
+#define IDC_FRAMESKIPAUTO8              228
+#define IDC_FRAMESKIPAUTO9              229
 #define IDC_8_BIT                       302
 #define IDC_16_BIT                      303
 #define IDC_32_BIT                      304
diff --git a/desmume/src/windows/resources.rc b/desmume/src/windows/resources.rc
index d8ff882ca..783a43289 100644
Binary files a/desmume/src/windows/resources.rc and b/desmume/src/windows/resources.rc differ
diff --git a/desmume/src/windows/throttle.cpp b/desmume/src/windows/throttle.cpp
index 0a296829c..785d671c8 100644
--- a/desmume/src/windows/throttle.cpp
+++ b/desmume/src/windows/throttle.cpp
@@ -1,5 +1,6 @@
-//THIS SPEED THROTTLE IS TAKEN FROM FCEUX.
+//THIS SPEED THROTTLE WAS TAKEN FROM FCEUX.
 //Copyright (C) 2002 Xodnizel
+//(the code might look quite different by now, though...)
 
 #include "../common.h"
 #include "../types.h"
@@ -8,9 +9,10 @@
 #include <windows.h>
 
 int FastForward=0;
-static u64 tmethod,tfreq;
+static u64 tmethod,tfreq,afsfreq;
 static const u64 core_desiredfps = 3920763; //59.8261
 static u64 desiredfps = core_desiredfps;
+static float desiredspf = 65536.0f / core_desiredfps;
 static int desiredFpsScalerIndex = 2;
 static u64 desiredFpsScalers [] = {
 	1024,
@@ -32,6 +34,7 @@ void IncreaseSpeed(void) {
 		desiredFpsScalerIndex--;
 	u64 desiredFpsScaler = desiredFpsScalers[desiredFpsScalerIndex];
 	desiredfps = core_desiredfps * desiredFpsScaler / 256;
+	desiredspf = 65536.0f / desiredfps;
 	printf("Throttle fps scaling increased to: %f\n",desiredFpsScaler/256.0);
 }
 
@@ -41,6 +44,7 @@ void DecreaseSpeed(void) {
 		desiredFpsScalerIndex++;
 	u64 desiredFpsScaler = desiredFpsScalers[desiredFpsScalerIndex];
 	desiredfps = core_desiredfps * desiredFpsScaler / 256;
+	desiredspf = 65536.0f / desiredfps;
 	printf("Throttle fps scaling decreased to: %f\n",desiredFpsScaler/256.0);
 }
 
@@ -49,78 +53,150 @@ static u64 GetCurTime(void)
 	if(tmethod)
 	{
 		u64 tmp;
-
-		/* Practically, LARGE_INTEGER and u64 differ only by signness and name. */
 		QueryPerformanceCounter((LARGE_INTEGER*)&tmp);
-
-		return(tmp);
+		return tmp;
 	}
 	else
-		return((u64)GetTickCount());
-
+	{
+		return (u64)GetTickCount();
+	}
 }
 
 void InitSpeedThrottle(void)
 {
 	tmethod=0;
-	if(QueryPerformanceFrequency((LARGE_INTEGER*)&tfreq))
-	{
+	if(QueryPerformanceFrequency((LARGE_INTEGER*)&afsfreq))
 		tmethod=1;
-	}
 	else
-		tfreq=1000;
-	tfreq<<=16;    /* Adjustment for fps returned from FCEUI_GetDesiredFPS(). */
+		afsfreq=1000;
+	tfreq = afsfreq << 16;
 }
 
-static bool behind=false;
-bool ThrottleIsBehind() {
-	return behind;
-}
-
-int SpeedThrottle(void)
+void SpeedThrottle()
 {
-	static u64 ttime,ltime;
-
-	if(FastForward)
-		return (0);
-
-	behind = false;
+	static u64 ttime, ltime;
 
 waiter:
+	if(FastForward)
+		return;
 
-	ttime=GetCurTime();
+	ttime = GetCurTime();
 
-
-	if( (ttime-ltime) < (tfreq/desiredfps) )
+	if((ttime - ltime) < (tfreq / desiredfps))
 	{
 		u64 sleepy;
-		sleepy=(tfreq/desiredfps)-(ttime-ltime);  
-		sleepy*=1000;
-		if(tfreq>=65536)
-			sleepy/=tfreq>>16;
+		sleepy = (tfreq / desiredfps) - (ttime - ltime);  
+		sleepy *= 1000;
+		if(tfreq >= 65536)
+			sleepy /= afsfreq;
 		else
-			sleepy=0;
-		if(sleepy>100)
-		{
-			// block for a max of 100ms to
-			// keep the gui responsive
-			Sleep(100);
-			return 1;
-		}
-		Sleep((DWORD)sleepy);
+			sleepy = 0;
+		if(sleepy >= 10)
+			Sleep((DWORD)(sleepy / 2)); // reduce it further beacuse Sleep usually sleeps for more than the amount we tell it to
+		else if(sleepy > 0) // spin for <1 millisecond waits
+			SwitchToThread(); // limit to other threads on the same CPU core for other short waits
 		goto waiter;
 	}
 	if( (ttime-ltime) >= (tfreq*4/desiredfps))
 		ltime=ttime;
 	else
-	{
 		ltime+=tfreq/desiredfps;
-
-		if( (ttime-ltime) >= (tfreq/desiredfps) ) // Oops, we're behind!
-		{
-			behind = true;
-			return 0;
-		}
-	}
-	return(0);
 }
+
+
+// auto frameskip
+
+static u64 beginticks=0, endticks=0, diffticks=0;
+static std::vector<float> diffs;
+static const int SLIDING_WINDOW_SIZE = 32;
+static float fSkipFrames = 0;
+static float fSkipFramesError = 0;
+static int minSkip = 0, maxSkip = 9;
+
+static float maxDiff(const std::vector<float>& diffs)
+{
+	float maximum = 0;
+	for(int i = 0; i < diffs.size(); i++)
+		if(maximum < diffs[i])
+			maximum = diffs[i];
+	return maximum;
+}
+
+static void addDiff(float diff, std::vector<float>& diffs)
+{
+	// limit to about double the maximum, to reduce the impact of the occasional huge diffs
+	// (using the last or average entry is a bad idea because some games do their own frameskipping)
+	float maximum = maxDiff(diffs);
+	if(!diffs.empty() && diff > maximum * 2 + 0.0001f)
+		diff = maximum * 2 + 0.0001f;
+
+	diffs.push_back(diff);
+
+	if(diffs.size() > SLIDING_WINDOW_SIZE)
+		diffs.erase(diffs.begin());
+}
+
+static float average(const std::vector<float>& diffs)
+{
+	float avg = 0;
+	for(int i = 0; i < diffs.size(); i++)
+		avg += diffs[i];
+	if(diffs.size())
+		avg /= diffs.size();
+	return avg;
+}
+
+void AutoFrameSkip_NextFrame()
+{
+	endticks = GetCurTime();
+	diffticks = endticks - beginticks;
+
+	float diff = (float)diffticks / afsfreq;
+	addDiff(diff,diffs);
+
+	float avg = average(diffs);
+	float overby = (avg - (desiredspf + (fSkipFrames + 2) * 0.000025f)) * 8;
+	// try to avoid taking too long to catch up to the game running fast again
+	if(overby < 0 && fSkipFrames > 4)
+		overby = -fSkipFrames / 4;
+	else if(avg < desiredspf)
+		overby *= 8;
+
+	fSkipFrames += overby;
+	if(fSkipFrames < minSkip-1)
+		fSkipFrames = minSkip-1;
+	if(fSkipFrames > maxSkip+1)
+		fSkipFrames = maxSkip+1;
+
+	//printf("avg = %g, overby = %g, skipframes = %g\n", avg, overby, fSkipFrames);
+
+	beginticks = GetCurTime();
+}
+
+int AutoFrameSkip_GetSkipAmount(int min, int max)
+{
+	int rv = (int)fSkipFrames;
+	fSkipFramesError += fSkipFrames - rv;
+	while(fSkipFramesError >= 1.0f)
+	{
+		fSkipFramesError -= 1.0f;
+		rv++;
+	}
+	while(fSkipFramesError <= -1.0f)
+	{
+		fSkipFramesError += 1.0f;
+		rv--;
+	}
+	if(rv < min)
+		rv = min;
+	if(rv > max)
+		rv = max;
+	minSkip = min;
+	maxSkip = max;
+
+	//printf("SKIPPED: %d\n", rv);
+
+	return rv;
+}
+
+
diff --git a/desmume/src/windows/throttle.h b/desmume/src/windows/throttle.h
index b2d3103e3..53a792606 100644
--- a/desmume/src/windows/throttle.h
+++ b/desmume/src/windows/throttle.h
@@ -1,11 +1,14 @@
 #ifndef _THROTTLE_H_
 #define _THROTTLE_H_
 
-void InitSpeedThrottle();
-int SpeedThrottle();
-bool ThrottleIsBehind();
 extern int FastForward;
 void IncreaseSpeed();
 void DecreaseSpeed();
 
+void InitSpeedThrottle();
+void SpeedThrottle();
+
+void AutoFrameSkip_NextFrame();
+int AutoFrameSkip_GetSkipAmount(int min=0, int max=9);
+
 #endif