MAMEWorld Forums - Hardware - Troubleshooting boot failure

A few months ago, my PC decided started hanging on startup. The hang only happens on a cold boot, restarting or even a shutdown and immediate restart works 100% of the time. About 90% of the time, it hangs during the Win7 "Starting Windows" animation. Rarely it will either boot successfully, or it will bluescreen. Bluescreen messages seem to be random, and don't seem to point to anything specific. On very rare occasions, I can see graphic glitches in the Windows animation, just before it bluescreens or hangs.

I don't have the time, money, or patience to start swapping out components randomly until the problem goes away, so I'm curious to hear suggestions as to what the most likely bad component is and/or ways to test. I've already run several passes of MemTest86 without error, so RAM doesn't seem to be a problem. My next thought is power supply? Could it be the voltages are sagging when it's started cold? Is there a way to test this without specialized equipment?