random CRASH/BSOD after loading game/section

[QUINTIX256]

In all honesty, I was having difficulty getting the memory to run at the advertised speed, see here;so I tried to up the base bus clock after changing the memory multiplier was not working. However, before the bios update, any attempt to run the base clock a little higher was met with an error on POST followed by a reset to the default speeds. So the APU/Memory was never running outside of stock specifications for more than a fraction of a second.

I also discovered that the only single slot 6670 available some months ago on newegg did not have GDDR5... after I had already committed to have it shipped. It ran fine, but I tried to OC the memory on it a while back (and only the memory) by a modest 10mhz. It wasn't long before there was graphical corruption, so I immediately reset it to the default speed.

I can't imagine either brief OC attempt causing any permanent damage.

Also, the crash and/or BSOD only has happened when a section is loading, not any other time.
Sometimes I can load a previous save point and get through a section without it crashing, but any saved game immediately before a section change would cause a crash (access violation pop-up dialogue) upon opening a door and loading for a bit.