Huge drops in FPS during games

[ima4ltrwrd]

hello all, I am having a serious issue right now with my computer... while im gaming I am having huge spikes in my FPS...ill be running a constant 70FPS and then have it drop down to 15FPS for a couple seconds. I have tried a million things to fix this, but I have yet to solve the problem.

My system:
p4 Prescott 3.0ghz HT CPU (stock speed)
1 GIG corsair XMS memory 2x512
200GB maxtor IDE HD
Radeon 256 MB x700 PRO (at stock speeds)
420 watt PSU
SB Audigy 2 value


I have done the following:

1. Used the newest drivers for the video card, omegadrivers
2. Reinstalled windows
3. Reinstalled windows and game on a different HD to see if the HD was broken
4. used different memory sticks
5. used different video cards
6. scanned for virus/adware
7. applied thermalgrease to cpu and bought new heatsink&fan running at 6000RPM
8. bought a new MOBO to test on
9. updated BIOS
10. changed bios settings
11. Monitored temps, 45 Idle, 55 running games

any suggestions would be appreciated, I cant stand my computer

 

[Sprooty]

do you have a stable internet connection, everything u have done above is everything i would suggest.

Does it happen on the new motherboard? because if it does id point my finger at your HD or Video card.

Whens the last time you defragmented?

 

[AnthraX]

What game? What are the graphics settings?

 

[metal11]

i used to have the same problem in ut2003 /4, but after a mobo and processor upgrade it went away

also, make sure your up to date on spyware / virus scans