Just reworked my Leadtek 6800nu. The backside piece is just a fancy backing plate - mostly
for asthetic purposes. If you think about it, many 6800 cards only have a plastic
backing plate there.
There isn't much too cool back there with the memory chips on the underside anyway.
Certainly nothing to mount a heatsink on. My card just had thick pads between the
back piece & card.
Now, the underside is another matter. The sink is stamped with raised pads to make
direct contact with the memory chips. Many other 6800 I've seen in the forums only
have a flat sink with thick pads similar to what's on the back of this one.
Oh, should also note that some have told me their Leadtek 6800nu did NOT have
the raised areas for the RAM. So there may be a couple versions of this card going around.
BTW ... was able to drop my GPU load temp by about 27c, and the Ceramique paste
hasn't broken in yet.
For some reason Leadtek saw fit to apply a brushed finish to the entire
surface. Not only that, the GPU contact patch was fairly warped as well. Likely
from the production process when the fan hole and RAM pads were stamped.
You can see images of the mod in this thread :::
http://forums.pcper.com/showthread.php?t=396369
P.S. - taking out that fan screen will help quiet the fan, and probably make it run a little cooler too.