My computer can run games like Gmod and whatnot, but after a few minutes, the framerate will suddenly drop to 2 or 1 FPS. It does not recover and I have to restart whatever game I was playing. It happens on stand-alone games like Gmod and GTA:SA, and on java games like Minecraft. It does not freeze up on Halo 1, for whatever reason. I did DxDiag but I'm not really experienced with this so I'm just posting what I think matters:
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System Information
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Time of this report: 8/17/2010, 16:35:56
Machine name: OHLORDY
Operating System: Windows 7 Home Premium 64-bit (6.1, Build 7600) (7600.win7_gdr.100618-1621)
Language: English (Regional Setting: English)
System Manufacturer: HP-Pavilion
System Model: NY464AA-ABA p6130y
BIOS: BIOS Date: 04/28/09 15:27:38 Ver: 5.11
Processor: AMD Phenom(tm) 9750 Quad-Core Processor (4 CPUs), ~2.4GHz
Memory: 8192MB RAM
Available OS Memory: 7936MB RAM
Page File: 3848MB used, 12020MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11
DX Setup Parameters: Not found
User DPI Setting: Using System DPI
System DPI Setting: 96 DPI (100 percent)
DWM DPI Scaling: Disabled
DxDiag Version: 6.01.7600.16385 32bit Unicode
Run one of these games in window mode and have task manager open by the side of it. Sort task manager so it shows the programs using the most cpu usage at the top. When the game slows down, check if any programs are using a very large amount of cpu usage