Hello everyone and thank you for the support you've given me in the past. I've explained my black-out problem long ago, and I've done a good hardware switch to try and solve the problem, but unfortunately it's not over yet. Before I switched any hardware I had this setup: Motherboard, that I don't know the manufacturer of Pentium 4 Northwood 3,2GHz ATI Radeon 9800 Pro 256mb 2x 512 Kingston Valueram PC3200 7200rpm Seagate 120gb 400W Matrox PSU Zalman 7000B-LED CPU-cooler And every now and then I experienced a black-out. It could happen daily or a couple of times a week. In any program or game that would load my graphics card heavily, it went black irregularly. The sound stopped playing as well, but the lights in num lock were still on. The only thing I could do was to power off my computer and turn it on again. Then I switched a lot of hardware, a few parts at once, and I now have this setup: AsRock 775Dual-VSTA Core 2 Duo E6300 1,86GHz ATI Radeon 9800 Pro 256mb 2x 512 Kingston Valueram PC3200 7200rpm Western Digital 80gb 500W Antec Smartpower 2.0 Zalman CNPS9500 CPU-cooler And I had a little hope, that my computer would be fixed. But lately, I faced the exact same problem. Well, actually not the exact same. On this setup it just restarts instead. After the restart I checked the event viewer and fell over this: It's in danish, but I'll try to translate it for you: After I saw that I read a bit about it, but couldn't find the exact same error message at Microsoft, so I tried disabling "Restart automatically on system errors" in advanced system options. Now, after disabling that, when my computer would normally have restarted, the screen just went blue and I could see white lines all around the blue screen. And nothing else would happen, just like when my computer went black before. I can take a picture of it next time it happens, if it's necessary. Now for the final conclusion.. What is really wrong? The only hardware I haven't switched yet is my RAM and my graphics card, but I can't afford to switch both of them after all of this. So I'll need to know if it's the RAM, the graphics card or something with the software? I've always used the newest graphics drivers by the way, so they're not the problem here. I've run Memtest86+ for 5 hours and 40 minutes to be exact, and it didn't find one single error. Thanks in advance.. I hope I gave you enough details to find the answer.