Just to add my own experience to this...
I started having this error earlier this evening...I was trying to run Speccy to get the type of RAM I had as my system was crashing and Memtest had been failed.
Even though I could run machine in safe mode, Speccy still gave me the same error.
I looked a bit deeper...
I went back to my BIOS and reset it to defaults, and voila, all instability in system disappeared and Speccy runs happily and it seems I do not have a hardware problem afterall either.
Then it dawned on me that I had tweaked my BIOS after my video card failed (disabling the slot etc etc) a couple of days before. I obviously did something my OS did not like and I guess I messed up my memory timings.
So, in summary, if any of you that are having issues are overclockers or have been messing around in your BIOS, have another look at those settings.
Hope this is of some help to someone...