I have tried everything under the sun to fix my crashing problem with my msi 7870 including and not limited to the following. RMA,drivers 12.3,18.104.22.168beta and 12.6beta,updated all software,BIOS, disabled/inabled stuff in BIOS like audio,default BIOS,OC BIOS,MEMTEST,PSU, fan speed for cooling, test psu,checked power connections,re set gpu on MB,downclocking/underclocking gpu . The only thing I can think of is my ASUS sabertooth x58 MB does not support this card.
The crash I get is a black screen, then I have to hold the power button down until the PC shuts down. I then restart the PC get the screen that says windows didn't shut down properly with the option safe mode. start windows normally ( sorry don't recall the whole message in that window). Most of the time after the PC boots up the GPU fan is at full speed for a few seconds.