Optimal timings

Console / mode	Dots per scanline / no. scanlines / @dotclk	OSSC base mode	Modified parameters	Notes	PC modeline
NES 256x240 @60.10Hz	341 / 262 / @5.37MHz(NTSC) [1][2]	256x240		To reduce jitter in couple topmost lines, try disabling ""Allow TVP HPLL2x" and/or using mask.	Modeline "ossc_nes_1280x720_60.08" 80.55 1280 1385 1510 1705 720 729 738 786 -hsync -vsync
SNES 256x239/224 @60.10Hz	341 / 262 / @5.37MHz(NTSC) @5.32MHz(PAL) [3]	256x240			Modeline "ossc_snes_1280x720_60.08" 80.55 1280 1385 1510 1705 720 729 738 786 -hsync -vsync
Mega Drive 320x224 @60Hz	427 / 262 / @?	320x240	H.samplerate=427
Mega Drive 256x224 @60Hz	341 / 262 / @?	256x240
N64 320x240 @60Hz	773.25 (?) / 262 / @12.18MHz(NTSC) [4]	320x240	H.samplerate=387, H.synclen=22, H.backporch=36	Every other visible dot (of 640) is interpolated
PSX 320x240 @60Hz	426.625 (?) / 263 / @6.71MHz(NTSC) @6.65MHz(PAL) [5] [6]	320x240	-
Saturn 320x240 @60Hz	427 / 262 / @6.71MHz [7]	320x240	H.samplerate=427
DC VGA @60Hz	858 / 525 / @27MHz [8]	480p	H active=640
GBI ULL 480p @59.72Hz	866 / 522 / @27MHz ?	480p	H samplerate=866 ?
CPS2 384x224 @59.64Hz	512 / 262 / @8MHz	320x240	H.samplerate=512, H.active=384, H.backporch=66
Seibu SPI	? / 293 (?)	?

Horizontal multiplication factors

Frame width is multiplied by an integer factor defined below while picture area is multiplied by the value in parenthesis to maintain correct aspect ratio. Vertical multiplication factor is defined directly by line multiplication mode. For example, consider 320x240 in line3x mode. Frame size is multiplied by 4 in horizontal direction, and by 3 in vertical direction to generate a frame of 1280x720 which is ideal for 720p output. However, picture area is multiplied by 3 in both directions so that effective area (960x720) maintains 4:3 ratio of the source.

	320x240	256x240 (4:3)	256x240 (8:7)
Line3x	4x(3x)	5x(4x)	5x(3x)
Line4x	4x	5x	5x(4x)
Line5x	5x*	6x*	6x(5x)*

• With Line5x, horizontal active and mask are adjusted internally so that frame width of 1600 or 1920 (depending on "Line5x format") is always generated. In 1920x1080 format, vertical active and backporch are also internally adjusted (-24 and +12) to generate suitable frame height.