Motherboard: Asus M4A87TD AMD Phenom X4 II SKT 640 3.00GHz AM3 box Memory: 2x Kingmax 2GB DDR3 1333MHz CL9 Video Card: Gainward GeForce GTX 460 768MB 192-bit DDR5 HDD: Western Digital 500GB SATA 7200RPM 16MB Caviar KX III Source: HPC-500-H12S Sirtec Case: Antec VSK-2000 Optical Drive: Optiarc AD-5260S Black Bulk Symptoms and other details: - It worked at work (5 hours uptime without reset) - With an extension of the Carrefour: 1. Reset after 2 minutes 2. Restarted: it resets again after 3-5 seconds 3. Restarted after an half an hour: it resets everything back to 3-5 seconds - With a protection strip V-Mark Extension SGE with shock protection: 1. Starts without problems 2. Install Windows 7 (64) + about 5 restarts for updates 3. After a few minutes monitor is showing : windows is shutting down 4. I power up again and now it only stays for a few seconds up then it shuts down again itself then power up again itself. I powering off and remove the cable from PSU 5. After a few hours i start it again without the DVD-drive, and it loads the windows 6. I shutdown from windows manually, and after 10 minutes it starts by itself just to shutdown again. Any suggestions what it might be? I would hate to have to bring it to warranty.