Degrading performance

[DarkDobe]

My new computer (2 months old now) is an HP Pavilion DV9000

-Intel Core2 T7200 @ 2.00 ghz (dual core)
-2048 Ram
-2x 120gb Hard Drives
-GeForce GO 7600
-64 Bit Operating System - Windows Vista Ultimate

Ive already started a topic along these lines in the Games forum, because thats where most of my problems arise, but as discussed and discovered there:

While playing some games (WoW, Call of Duty 2, FEAR, and Unreal Tournament), my computer runs just fine for about 15 minutes, and then intermittently starts degrades to sub 1fps rates. The odd thing here is that my CPU usage jumps to 100% during these times, which last about 5-15 seconds, and then return to normal. I have no clue what could be causing this, and it's only been happening for a few weeks.

Viruses and spyware are scanned for daily, disks are defragmented, and I've turned off unnecessary programs in the background now, yet the problem still arises.

It was suggested to post the issue here in this section, as the 100% cpu use problem is throwing people for a loop.

 

[Tedster]

Vista has serious issues with games and is not recommended for most games. Try running in XP compatibility mode.

 

[DarkDobe]

... You know I think you might be right about that, though why it would take an odd month to show this annoying flaw is beyond me. I'll give it a shot.

 

[DarkDobe]

Well, running in XP compatibility makes some difference. The overall framerate of the game drops slightly, and fluctuates between 20 and its usual 35, and the complete slowdowns/100% cpu use problems seem allot more sparse. I've installed a new antivirus program (Kaspersky) and am cleaning out the computer more thoroughly, defragging, and trying whatever I can to fix this annoyance.