Does the power supply have two 6-pin PCI-E connectors or does it only have one?
If you're overclocking return all settings back to stock to see if that reduces or eliminates the BSODs.
Have you downloaded and run memtest86+ to determine if any of your memory modules are faulty? Run it through at least one complete cycle of tests. If all of the memory modules are working correctly you should get no error messages in memtest86+.