Upgrading a 2005 system....

[SilentMichael]

Thanks for the suggestions.

you didnt say what res your gaming at but im guessing its a 17 incher or the like since your rig is pretty dated, in this case a 4850 512 will be plenty. and right on budget.

EDIT: i see there are no 4850 512mbs no more, then looks looks like a 1gb or gts 250 would be your best bet as they said above.
Newegg.com - EVGA 512-P3-1150-TR GeForce GTS 250 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready SLI Supported Video Card - Desktop Graphics / Video Cards

Unless you are gaming at a high resolution (>=1680x1050) there isn't any reason to get a gpu with 1gb of memory.

Newegg.com - XFX HD-485X-YDFC Radeon HD 4850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card - Desktop Graphics / Video Cards

Actually, the monitor that I am using with the computer has a resolution of 1680x1050, would it really make a big difference if I got one video card over another? Also, is there an nvidia equivalent of the video card you posted, Puddle Jumper, or would it just be the GTS250 that was already posted?

 

[baron5]

yep the gts 250 IS a 9800gtx, which is the head-to-head competitor of the 4850, with the 4850 coming out slightly better, i would just stick a 4850 1 gb in your system. Be fine for your resolution at your budget.

 

[Trotter]

Additional RAM would really help you out. Here's a good set:
Newegg.com - G.SKILL Value 2GB (2 x 1GB) 184-Pin DDR SDRAM DDR 400 (PC 3200) Dual Channel Kit System Memory Model F1-3200PHU2-2GBNT - Desktop Memory
$59 w/free shipping. DDR ain't cheap anymore.

If you are playing Source games, you can get by without top-o-the-line graphics power. I am running a 3850 and it can handle all of them perfectly.
Newegg.com - SAPPHIRE 100248L Radeon HD 3850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card - Desktop Graphics / Video Cards
$60

If you can get your hands on a dual core later on it would be great. I traded for mine a ways back.

 

[veg1992]

Unless you are gaming at a high resolution (>=1680x1050) there isn't any reason to get a gpu with 1gb of memory.

Newegg.com - XFX HD-485X-YDFC Radeon HD 4850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card - Desktop Graphics / Video Cards

You are my hero for finding that ....

yep the gts 250 IS a 9800gtx, which is the head-to-head competitor of the 4850, with the 4850 coming out slightly better, i would just stick a 4850 1 gb in your system. Be fine for your resolution at your budget.

You mean 9800GTX+

The GTS 250 is a blatant renaming scheme to get more people to buy their cards because their name seems "higher-end" than before.