Graphical Lock Up

Hi, I’ve started getting these lock ups when playing both single and multiplayer. When playing the screen seems to lock up, for example I play roleplay on the EvoCity map and after playing around half an hour it starts to lock up once every 10 seconds for about a second not allowing me to move or do anything. Then it keeps locking up longer and more frequently until it’s almost constantly locked up only giving slight half a second jumps where it isn’t. I then have to hold the power button on my computer in until it switches off. When playing on EvoCity 2 it locks up almost immediately and im lucky if I get 5 mins before I have to restart my computer, but when its not locked up im getting no lag at all and it runs very smoothly. What I don’t understand is I have a 2.5GHz Q6600 quad core proccessor and a 8600 GTS graphics card and im getting these problems where as my brothers computer has a 2.69 7750 Dual Core proccessor and a 9400 GT Graphics card and he gets no lag at all and is on the same network. I’m convinced this has something to do with the graphics but ive tried lowering the settings, reinstalling steam, gmod and even xp. Thanks for any help, Glennlh.

Drivers, GPU it’s self
Post Temps with HWmonitor
Update Drivers.

When I reinstalled XP I installed the latest graphics drivers. My graphics cards temp tops at around 66c.

Is this only in GMod or also in other games? if you also experience this in other games i suggest you ask it in the Technical Support

I only seem to get this in gmod, havn’t yet experienced it in any other games. I’ll give CSS a try later and see if it works.

Tried a few other games, seems that there no problems with them.

Actually after playing other games for a while it starts to lock up on them the components are overheating as well so it looks like a hardware problem after all then. Here’s my computer specs:

Asus P5B
Intel Q6600 Quad Core 2.4GHz
GeForce 8800 GTS
2GB 800MHz RAM

Here’s a screen from SpeedFan when my computer started to freeze up: