diff --git a/src/g_shared/sbarinfo_commands.cpp b/src/g_shared/sbarinfo_commands.cpp
index b4ce895488..62043a6a82 100644
--- a/src/g_shared/sbarinfo_commands.cpp
+++ b/src/g_shared/sbarinfo_commands.cpp
@@ -1732,6 +1732,8 @@ class CommandAspectRatio : public SBarInfoCommandFlowControl
 				ratio = ASPECTRATIO_16_9;
 			else if(sc.Compare("16:10"))
 				ratio = ASPECTRATIO_16_10;
+			else if(sc.Compare("17:10"))
+				ratio = ASPECTRATIO_17_10;
 			else if(sc.Compare("5:4"))
 				ratio = ASPECTRATIO_5_4;
 			else
@@ -1750,6 +1752,7 @@ class CommandAspectRatio : public SBarInfoCommandFlowControl
 			ASPECTRATIO_4_3 = 0,
 			ASPECTRATIO_16_9 = 1,
 			ASPECTRATIO_16_10 = 2,
+			ASPECTRATIO_17_10 = 3,
 			ASPECTRATIO_5_4 = 4
 		};
 
diff --git a/src/menu/videomenu.cpp b/src/menu/videomenu.cpp
index 0d15904635..3e8f18ea83 100644
--- a/src/menu/videomenu.cpp
+++ b/src/menu/videomenu.cpp
@@ -83,15 +83,15 @@ int OldWidth, OldHeight, OldBits;
 static FIntCVar DummyDepthCvar (NULL, 0, 0);
 static BYTE BitTranslate[32];
 
-CUSTOM_CVAR (Int, menu_screenratios, 0, CVAR_ARCHIVE)
+CUSTOM_CVAR (Int, menu_screenratios, -1, CVAR_ARCHIVE)
 {
-	if (self < 0 || self > 4)
+	if (self < -1 || self > 4)
 	{
-		self = 3;
+		self = -1;
 	}
 	else if (self == 4 && !vid_tft)
 	{
-		self = 3;
+		self = 0;
 	}
 	else
 	{
@@ -213,7 +213,7 @@ static void BuildModesList (int hiwidth, int hiheight, int hi_bits)
 	bool letterbox=false;
 	int  ratiomatch;
 
-	if (menu_screenratios >= 0 && menu_screenratios <= 4 && menu_screenratios != 3)
+	if (menu_screenratios >= 0 && menu_screenratios <= 4)
 	{
 		ratiomatch = menu_screenratios;
 	}
diff --git a/src/v_video.cpp b/src/v_video.cpp
index f2436862bf..cef81aba54 100644
--- a/src/v_video.cpp
+++ b/src/v_video.cpp
@@ -1635,16 +1635,25 @@ CUSTOM_CVAR (Int, vid_aspect, 0, CVAR_GLOBALCONFIG|CVAR_ARCHIVE)
 // 0: 4:3
 // 1: 16:9
 // 2: 16:10
+// 3: 17:10
 // 4: 5:4
 int CheckRatio (int width, int height, int *trueratio)
 {
 	int fakeratio = -1;
 	int ratio;
 
-	if ((vid_aspect >=1) && (vid_aspect <=4))
+	if ((vid_aspect >= 1) && (vid_aspect <= 5))
 	{
 		// [SP] User wants to force aspect ratio; let them.
-		fakeratio = vid_aspect == 3? 0: int(vid_aspect);
+		fakeratio = int(vid_aspect);
+		if (fakeratio == 3)
+		{
+			fakeratio = 0;
+		}
+		else if (fakeratio == 5)
+		{
+			fakeratio = 3;
+		}
 	}
 	if (vid_nowidescreen)
 	{
@@ -1662,6 +1671,11 @@ int CheckRatio (int width, int height, int *trueratio)
 	{
 		ratio = 1;
 	}
+	// Consider 17:10 as well.
+	else if (abs (height * 17/10 - width) < 10)
+	{
+		ratio = 3;
+	}
 	// 16:10 has more variance in the pixel dimensions. Grr.
 	else if (abs (height * 16/10 - width) < 60)
 	{
@@ -1680,7 +1694,7 @@ int CheckRatio (int width, int height, int *trueratio)
 	{
 		ratio = 4;
 	}
-	// Assume anything else is 4:3.
+	// Assume anything else is 4:3. (Which is probably wrong these days...)
 	else
 	{
 		ratio = 0;
@@ -1693,16 +1707,21 @@ int CheckRatio (int width, int height, int *trueratio)
 	return (fakeratio >= 0) ? fakeratio : ratio;
 }
 
-// First column: Base width (unused)
+// First column: Base width
 // Second column: Base height (used for wall visibility multiplier)
 // Third column: Psprite offset (needed for "tallscreen" modes)
 // Fourth column: Width or height multiplier
+
+// For widescreen aspect ratio x:y ...
+//     base_width = 240 * x / y
+//     multiplier = 320 / base_width
+//     base_height = 200 * multiplier
 const int BaseRatioSizes[5][4] =
 {
 	{  960, 600, 0,                   48 },			//  4:3   320,      200,      multiplied by three
 	{ 1280, 450, 0,                   48*3/4 },		// 16:9   426.6667, 150,      multiplied by three
 	{ 1152, 500, 0,                   48*5/6 },		// 16:10  386,      166.6667, multiplied by three
-	{  960, 600, 0,                   48 },
+	{ 1224, 471, 0,                   48*40/51 },	// 17:10  408,		156.8627, multiplied by three
 	{  960, 640, (int)(6.5*FRACUNIT), 48*15/16 }	//  5:4   320,      213.3333, multiplied by three
 };
 
diff --git a/src/win32/hardware.cpp b/src/win32/hardware.cpp
index 6408e9279b..6b3f40f1cd 100644
--- a/src/win32/hardware.cpp
+++ b/src/win32/hardware.cpp
@@ -338,7 +338,7 @@ CUSTOM_CVAR (Float, vid_winscale, 1.f, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 
 CCMD (vid_listmodes)
 {
-	static const char *ratios[5] = { "", " - 16:9", " - 16:10", "", " - 5:4" };
+	static const char *ratios[5] = { "", " - 16:9", " - 16:10", " - 17:10", " - 5:4" };
 	int width, height, bits;
 	bool letterbox;
 
diff --git a/src/win32/win32video.cpp b/src/win32/win32video.cpp
index d82744ef79..494df774d5 100644
--- a/src/win32/win32video.cpp
+++ b/src/win32/win32video.cpp
@@ -449,6 +449,8 @@ void Win32Video::AddLowResModes()
 {
 	ModeInfo *mode, *nextmode;
 
+	AddMode(1024,600, 8, 600, 0);
+
 	for (mode = m_Modes; mode != NULL; mode = nextmode)
 	{
 		nextmode = mode->next;
diff --git a/wadsrc/static/menudef.txt b/wadsrc/static/menudef.txt
index 03f0baeac0..e27ba1036e 100644
--- a/wadsrc/static/menudef.txt
+++ b/wadsrc/static/menudef.txt
@@ -1429,26 +1429,29 @@ OptionMenu ModReplayerOptions
 
 OptionValue ForceRatios
 {
-	0.0, "Off" 
-	3.0, "4:3" 
-	1.0, "16:9" 
-	2.0, "16:10" 
+	0.0, "Off"
+	3.0, "4:3"
+	1.0, "16:9"
+	5.0, "17:10"
+	2.0, "16:10"
 	4.0, "5:4"
 }
 OptionValue Ratios
 {
-	0.0, "4:3" 
-	1.0, "16:9" 
-	2.0, "16:10" 
-	3.0, "All"
+	0.0, "4:3"
+	1.0, "16:9"
+	2.0, "16:10"
+	3.0, "17:10"
+	 -1, "All"
 }
 OptionValue RatiosTFT
 {
-	0.0, "4:3" 
-	4.0, "5:4" 
-	1.0, "16:9" 
-	2.0, "16:10" 
-	3.0, "All"
+	0.0, "4:3"
+	4.0, "5:4"
+	1.0, "16:9"
+	2.0, "16:10"
+	3.0, "17:10"
+	 -1, "All"
 }
 
 OptionMenu VideoModeMenu