Apoppin:
For the LAST time, I AM NOT talking about *VRAM* overheating and losing performance to error correction. I am theorizing that the *VRMs* could be overheating, which would cause the CORE (*not* the memory, that's COMPLETELY different) to throttle.
If you still can't grasp that, maybe this will help:
VOLTAGE REGULATOR MODULE != VIDEO RANDOM ACCESS MEMORY
Again, I'll lay it out for you. When the VRMs on a 5870 overheat it causes the card to throttle, which reduces performance.
Granted this is only a theory, and it could just as easily be proven wrong given the methodology I've described twice now. The simple fact of the matter is that when you apply a lot of voltage like you did to obtain your overclock, VRMs need to work harder and they get hotter. Any game that loads the 5870 to a significant degree is then more likely to exhibit throttling, just like furmark already does at stock clocks.
I don't know if you've been beating around the bush, or you simply don't know the difference between VRAM and a VRM, but either scenario isn't good if you want people to take you as a serious reviewer. Sorry for the all caps, but dude, you've exhausted the ways I have to get through to you.
Again, please don't come back and respond that you've tested the memory at 1150 and 1200MHz. That is not what I am talking about