the dx48bt2 motherboard does not have any diagnostic lights.
EDIT: I did a diagnostic test with Hot CPU Pro 4. It found no problems with my motherboard or memory.
EDIT: Scratch that. The problem with the RAM is confirmed. I was playing Halo 2 when my computer suddenly died (no blue screen this time). It tried to reboot but I got the 3 beeps from the motherboard, indicating that something was wrong with the RAM. I opened up the case and tried switching the RAM around. No luck. I then tried each stick by itself in the first slot. That did work, I then tried using two identical sticks that I had accidently purchased (remember, I bought 8GB only to find out that my motherboard would only accept 8GB if it was 1333Mhz or under.) That worked fine. This tells me that something is clearly wrong with the RAM. I have decided to take the offer of the RAM manufacturer up and trade my RAM for a very similar model (that hopefully works.) Unfortunately, this means that I will be without a computer of my own for a few weeks (at the most). Right now I am on my sisters crappy Dell from the stone age (It runs Windows 2000!)