I think I may have one or more faulty RAM bays on my board - I have 4 bays in total, and I have 4GB of RAM in my PC using 2x2GB sticks. If I install the sticks in bays 2 and 4 everything works with no problems, but if I move the sticks to bays 1 and 3, I get no display. Then if I put 4x2GB sticks in to make 8GB, Windows boots but then blue screens. What's going on here? The BIOS is up-to-date. Thanks.