Hello everyone. I've had my computer for around 2 years now, and I've been experiencing a very annoying problem through those 2 years. Now I've decided to finally try and get some proper help. You'll get my computer specs first: Pentium 4 HT Northwood 3,2GHz ATI Radeon 9800 Pro 256mb 2x512mb Kingston Valueram PC3200 400W PSU Windows XP Home Edition SP2 fully updated. The problem is, that my computer irregularly goes black after an uncertain amount of playing time. It happens in any newer full-screen game (World of Warcraft, Warcraft 3, Counter-strike(rarely)) - my monitor goes black, the monitor power symbol starts flashing as if it had no signal, my sound stops playing, BUT my fans are still running and the light on "num lock" is still on. To start the computer again, I have to turn the power off and on again, as nothing else responds. Sometimes I can play for hours without experiencing the problem - it's happening irregularly. I don't think it can be the drivers, as I've been formating my computer several times through the past 2 years, and I've always downloaded the newest ATI driver and still had the problem. I can say already, that my temperatures are a bit high. I'm running with only one side on my case or else the CPU-temp goes beyond 67 celcius degrees. Right now it's max 65 celcius degrees, which I know is too high, but would the CPU-temp cause a black-out? It goes black with or without both sides on my cabinet. I've run the "Windows Memory Diagnostic Tool" under boot for 30 minutes, which didn't give any errors. My computer should be 100% spyware and virus free, as I've run full-scan with several anti virus and spyware scanners just to make sure. I am very frustrated, that I can't find a proper solution, and I wouldn't like to spend a fortune on making it work again. I really hope you can help me fix the problem. Thanks in advance.