I built a new computer for use in my office at work, it seems to lock up about 1-2 times daily. There are no error messages, no rebooting, etc. It just locks up, the cursor doesn't move and the computer doesn't respond to any keyboard commands. It's a fairly basic system, has an SSD, i3, 2GB of DDR3 RAM. I used CoreTemp to make sure the CPU wasn't overheating or something...though I think that would cause reboots or turning it off rather than locking up. It sounds like a RAM issue to me, but I wanted the expert opinions here. I'd like to run MemTest on it but the coworker needs to use the PC to work so I can't really do that right now. Are there any diagnostic programs I could run within Windows while she works?