my game perfomanceis slower than before

[loganz]

Until two weeks ago, I was able to run games on my pc very smoothly.highest perfomance. Now all my games are very slow, laggy, or choppy(A couple examples are swat 4.scarface,farcry.i can play this before with ahighest settings,but now slow with very low settings.i have tried downloading game booster, regcleaner.adisk fragmenting, closing other programs while playing and i have also updated my graphic card.with all my driverinstalling new windows.format c.but still slow.any ideas.plizz dont say upgrade your ram. graphics card.etc.im sure i can play most of the games with ahigher settings before.please help.help.help.me
here is my specs.
windows xp sp3,
P4.3.00ghz
ram-1gb
graphics card-8400gs

[killerb255]

Check your CPU and video card temps.

OCCT: http://www.ocbase.com/perestroika_en/index.php?Download

Since you've just formatted, it's unlikely that you have malware unless the PC just recently got (re?)infected.

Also go to nVidia's site and download the latest drivers for your video card.