Widescreen Monitors VGA and DVI throughput

So, Ive just recently got a computer up and running again. Apparently I just found out that we can all thank my roommate for blowing his hair dry and blowing out the fuses.....and my computer. oh well. upgrades happen.

So the deal is this: I cannot for the life of me figure out why some games won't run well at all. I know that sounds like a gaming question but I think my problem might be the fact that my widescreen monitor is only VGA.

CPU - Pentium D 805 [standard clock rate] 2.66 dual core.
RAM - 2gb dual channel DDR2-667 running at DDR2-533
VIDEO - Gigabyte 256mb GDDR3 GeForce 8600 (GV-NX86T256H) i think its 540/1600 mhz or maybe 575/2000.
Monitor - Acer AL2016W with 16:10 ratio. this monitor ONLY has VGA.

Background: now I know for a fact that my computer has got newer components them my roommate. He's got an Athlon 3x00 or 4x00 (non dual core! probably 64bit, but not running 64bit OS) 768mb ram, and an earlier 8600 256mb. probably running high 4xx-525mhz. And he's got some 3x" LCD TV with DVI/HD etc all that fun stuff. His doom 3 looks f&*(&*( gorgeous, and MAYBE drops to sub 30 frames per second in highly active areas of the game. but stays steady 60/59 through com_showfps 1. NOW with the same settings and all that or if i even try lower resolution, it gives me 7FPS when i see fire. if im in an elevator i get about 20-30FPS. if im in a room with ONE guy, its like 12.5FPS

Its gotta be the VGA cable. but nowhere on the net can i find any information on this. Seriously it shouldn't be that hard for a computer geek to figure this out.


\\StuckInLimbo FeelLikeHell

What driver are you using?

When did you do your last disk clean-up?

When's the last time you de-fragged your hard drive?

Virus scan, spyware scan,etc,etc...?