Low Fps And No Idea

[Rival]

I have a quite decent computer with the specs

Gigabyte 9800 GT,
Intel Q8200,
Kingston 2 Gig Ram 1099mhz,
motherboard GA-EP43-DS3,
AntecTP3-650, 650W PSU.

However, running games such as Counter Strike Source on highest or lowest settings using its video stress test give my computer an average rating of less than 30 fps. I've also checked with other game titles such as Prince of Persia running on high and low settings and received consistent stutters. This is also evident in any other game such as Grand Theft Auto IV or poor loading times for Warcraft III. The problem occurred after i decided to format and after format to Windows XP SP3, all of these gaming problems appeared. Drivers are all updated to the most recent from nvidia, and i have formatted again with a friends XP SP3 to make sure it wasn't just the OS. I've also checked using CPU-z and GPU-z if my settings are correct and nothing has been overclocked or underclocked, resting on its default settings. Everything worked fine before the format in terms of gaming quality. So I'm not sure what exactly is causing the problem after a fresh format.

Please help.

 

[nosebleedXD]

what os was your computer running at before you reformatted

 

[tragicallyhip]

I would reformat and only use xp sp2 ,sp3 is not really needed ,I am gaming with SP2 and thought about installing SP3 but after reviewing the change log in SP3 I realized it was a non starter.Formatting is a big pain! but what can you do?
good luck and keep posting