Getting MAME to use entire 25 inch screen

[JPACMAN]

Hi,
I just got an JPAC and hooked up my PC to the 25 inch monitor in my cabinet. This was a Soul Edge game previously. I used Arcadeos and MAME .61 for DOS and am able to get some games to come up, but they only display in the center of the screen and utilize only approximately half of the available screen area. How can I get MAME/Arcadeos to take advantage of my 25 inch monitor?

One thing I should mention, Arcade OS seems to take full advantage of the large monitor, it's only when the games start that it isnt using the full screen. Adjusting the resolution setting in AOS doesnt seem to help or change anything.

On a side note my screen is a little jittery in the sense that the image seems to bounce up and down an inch or so  every couple of seconds. Anyway to adjust this. I have a GEforce 3 card driving the display. Not sure of the brand name, it came with my Dell.

Thanks for the help! I'm very new to the mame world so any info would be helpful. If there are any tutorials available I'd appreciate it a pointer to them. I have read the FAQ on this site.

[Superdude]

Advance Mame.

^^^^^^^^^^
answer is above.

[Superdude]

oh wait....
You can turn on hardware stretching too in regular mame

[roboto]

yeah-from dos
edit mame.cfg

Harware stretching-try that, otherwise, you might think about a different video card if you don't already have a good one.
LIAM