I have 9.2.1 on one of mine, and it's quite solid.

I second the advice from others that you should throttle back to the minimum configuration (especially the removal of the USB cards) and work your way back up.

Another possibility is a flaky power supply. I've encountered more than one case of a marginal supply. You may want to measure the 5V and 12V supply voltages to preclude this as a culprit. Also, carefully inspect the motherboard for any telltale smudges from leaking caps, pram battery, etc.