Check all your connections are tight then take out the memory sticks and re-insert, making sure they snap in positively and are inserted in the right order (if applicable). I had a brand new build do this. It turned out to be a faulty motherboard but we knew the machine checks the memory first. Question is, if it doesn't check out, whether it can bring everything to a halt. So it could either be faulty memory or a fault in the board. The tricky part is finding out which...
Dr. V