MAMEWorld Forums - Ultimarc - Re: Arcade VGA 5000 with HDTV display rotated

Just as an FYI, there is some benefit of using the arcade vga with a non 15khz monitor. All of it's low resolution modes like 320 x 240 at 60hz are also available on 31khz displays.

While waiting for my jrok to arrive, I used my arcade vga with a standard vga crt monitor and 240p is selectable in mame. I don't know how they manage to output 320 x 240 at 60hz with a 31khz horizontal rate but that is what they do. Normal vga cards can't do that. 320 x 240 fills the screen with no hardware stretching etc.

On their site, they correctly point out that 320 x 240 on a vga monitor will not look exactly like the arcade monitor because the dot pitch is too fine but it is a noticeable improvement over a regular card.

I combined it with an extron scan converter which converts the 31khz 320 x 240 output to 320 x 240 15khz through s-video for my Sony trinitron crt tv. The result is impressive and much better than anything I could achieve with HLSL on my lcd.

I now use a jrok encoder to convert the 15khz rgb to s-video directly. The result looks almost the same as when I was using the scan converter but it moves better. I always though emulated games had missing frames even when the FPS looked accurate. With the arcade vga, they move just like the original board.

The arcade vga can putput 320 x 240 on an lcd monitor too although there is less of a point because it has to be scaled to fit the native resolution.

There is a big difference between the resolution that the games are rendered at and the display resolution. On a fixed pixel display like an lcd monitor, the image usually looks best when it matches the displays native res. it is poor scaling that is responsible for most of the image problems.

I have a 1024 x 768 lcd projector and mame looks best when all games are set to that resolution (regardless of what the original res was).

CRT vga monitors have no native resolution and games look best at their native resolution, even at 31khz.

For any flat panel monitor, a standard card and HLSL will give the best results but nowhere near as good as a 15khz tv or monitor. If you already have the arcade vga, why not pick up one of the many free crt tv's off craigslist? If you get one with component input then converting the 15khz vga output is not particularly difficult.

The arcade vga is meant to replicate the video logic of the original board where a standard 480i at 30hz signal is manipulated to make the odd and even fields overlap (but not repeat) to produce a 60hz refresh rate. I don't have the technical knowledge to understand how this works when it is output as a real progressive signal. To my eye, it looks like 480i is just doubled to produce 480p at 60hz which may explain why it looks like some animation frames are missing on a flat panel monitor. It could also be the post processing from direct 3d / HLSL.