Hello, I just finished building a computer and got it working within a few minutes, Installed windows 7 64bit and then proceeded to install all the updates required. I shut it down and plug the graphic card into the motherboard, turn on the PC and everything turns on like it normally should, but after 10 to 15 seconds it shuts off and automatically turns on a few seconds later and this is non-stop until I shut down the power from the power supply. The motherboard is a Biostar H61ML and the graphic card is a GeForce 8400GS DDR2 512MB PCI. The system has 8GB Ram, Intel Quad-Core 3.10GHz 2400, Cooler Master 500w Extreme Power Plus Power Supply, and the Cooler Master Hyper 212 Plus CPU Cooler. Is there a problem with the graphic card or the motherboard and graphic card are not compatible with each other? Thank you.