ASUS are pretty expensive.
And what other video card under 100 bucks would you recommend for a 480w psu?
Definitely get a 5570. Its a $80 dollar card that uses 45 watts of power. And it packs a punch for its power consumption and price. I recommend XFX Instead of Saphire Btw. First they look better, second, they work better.
Your rig im imagining would get around 15 on a low quality map. max around 60-70. - Thats looking into a wall relitively. Honestly Gmod is the worst benchmark you can use.
Runs gmod at max settings at about 30-50 fps. L4D2 which is a more stable game because of custom content and non crap mapping at 32 fps average, very stable. Thats cause I have a 32 bit os and 3 gigs of ram. also a 2.2 ghz quad-core. If you had something like my new rig it could push out about 60 fps.
My GeForce 9500GT 512MB VRAM pwns teh jooz.
Yeah and my Asus Geforce 8500 was a good card.