I've always had this problem with newer games, it's happened with Alien Swarm, TF2, Tropico 3, Borderlands, and many more. Older games like UT99 and Quake will perform fine, even WoW. In most games my fps will drop down to 7 or 8 for about ten seconds at a time, and then go back up for the same amount of time and rotate back and forth.
I've checked my temperatures and nothing is overheating, they barely go up at all. I've been thinking about upgrading my processor, but I've seen people with better specs having the same problem. I've even recorded a video of the screen in TF2 while staring at the ground: http://www.youtube.com/watch?v=rTc_GyK5Zgc
I'm just off a fresh reformat and it hasn't solved the problem. System specs below:
Mainboard : Asus P5GC-MX
Chipset : Intel i945G/GZ
Processor : Intel Pentium 4 540 @ 3200 MHz
Physical Memory : 4096 MB (4 x 1024 DDR2-SDRAM )
Video Card : NVIDIA GeForce 8800 GT
Hard Disk : WDC (120 GB)
CD-Rom Drive : SAMSUNG CD-R/RW SW-208B
DVD-Rom Drive : PIONEER DVD-ROM DVD-115
Monitor Type : Emerson -
Network Card : L2 Fast Ethernet 10/100Base-T Controller
Operating System : Microsoft Windows XP Home Edition 5.01.2600 Service Pack 3
DirectX : Version 9.0c
A background running application could cause that (security, disc management, etc). If you have a fire wall, try disabling that (including the windows one).
I guess you do have the newest drivers since you are after reinstall...
Make sure the integrated GPU is fully disabled. You might want to upgrade that though, including your CPU, heh.
If you have some energy saving utilities or something (like AMD's Cool'n'Quiet), try disabling that too.
Lets face it, theres no way a Pentium 4 is capable of running modern games. The RAM is OK (I'm assuming its at least 667Mhz...), and the 8800GT is getting on, but still a decent budget card. But a PENTIUM 4?
Games today require at least a Core 2 Duo, if not a Core 2 Quad to run well. They may be capable of running on a Pentium 4, but not well and certainly not with options turned on their highest levels.
pentium 4 ?????
that processor now is the piece of crap.... it cant handle modern games ...!
i had a same problem with you 2 years ago...
i use 8800 ultra on pentium 4 and the performance is almost the same with x1650 pro !