windows 7 - Why is my PC freezing in 3D games?

This is the follow-up for this thread. Since I wrote it I've done several testing but so far cannot get my computer to run 3D apps correctly.

First let me quickly remind you the problem: my machine works fine in normal desktop apps. However when I start any 3D app (like games) it works for 20-30 minutes and freezes the computer. It happens all the times with every game I tried (and that was quite a few).

Computer specs are as follows: Core 2 Duo E8400, ASUS P5QL-E, 6GB RAM (2x1GB, 2x2GB), GeForce 9800 GT, Yesico SilentCool SC560-AS12CF (560W) power supply, 2x500GB HDDs in RAID0, Win7-64bit

What I've tested so far:

• memory - memtest was running for the whole night, not a single problem found, I also tried removing some of the modules, didn't make any difference


• graphics - I've borrowed two graphics card, GeForce 8800 GT (which is pretty much the same as my 9800 except it has bigger cooling unit) and Radeon HD 4870, Radeon didn't freeze my computer but after playing for half an hour or so it started turning the display on and off every few seconds, GeForce 8800 first froze my computer like my old card and then after I set up the fan to run at 100% all the time it was behaving more less like Radeon, I also tested the temperature of the GeForce and it was 55 degrees Celsius when computer booted and aroud 5 degrees hotter when computer started causing problmes so it's not much of a difference there, I've also tried my card on my friends PC and we couldn't make it to freeze even after 2-3 hours of intensive gaming


• power supply, I've change it to some old one I had in the closet, nothing changed, plus this one is much better class then old one so I don't suspect it is the problem

Does anyone has any other suggestion what I could check to find the problem? Unfortunatelly I don't have a possibility to try another mainboard or processor at the moment but I suspect that if these parts were problematic it would crash normal desktop apps as well.

Answer

Don't forget that 3D gaming is one of the most intensive things you can do on a PC - both for the CPU and the graphics card, so it's not surprising that it works for "normal" desktop apps.

Have you tried and 3D apps like AutoCAD or 3D Studio MAX? You can download trial versions of these so you should be able to find one. Open a large scene, render it and see if your PC crashes.

Given what you've said you've tried it looks like it's pointing to a problem with the CPU - is it overheating? How's it cooled? If it's a fan, check that it's connected and spinning freely. Also check that there is good thermal contact between the CPU and heat sink.

Another thing to try is to turn the game graphics down to minimum - screen resolution, texture size etc. and then run the game. If this works OK, turn one setting at a time back up to maximum (or the recommended value) and see where it starts failing. If it's the texture size then that would point to a memory fault (for example).