I was skeptical about the overclockability of the card to be honest. As it
consumes more power for the additional memory, the addition of inductors to the
circuitry of the original 6800 Ultra makes it seem like a tough card to
overclock. Furthermore, the additional 256Mb memory may make it tougher to
However, our testing gave us a pleasant surprise. Let us make an overclocking
comparison between the 256Mb Ultra and the 512Mb Ultra.
With default cooling on the XFX 256Mb 6800 Ultra, we were able to overclock
it to 450/1220Mhz stable through 3D Mark 2005 without artifacts.
We tried to run the 512Mb Ultra at the same speed with the default cooling
and it was stable and artifact-free as well.
While the 256Mb Ultra topped out at 450/1220Mhz, the 512Mb went onto
460/1320Mhz, artifact-free! That’s a great overclocking result with just
default cooling and no mods.
We are pleasantly surprised at how overclockable the memory is on this card.