Depends on the GPU (actual core, not 6800 XT) the card has.
No doubt some of them might be able to handle it, but other cards (from the same company, just diff revision) will not.
Recommending a (PCIe x16) GeForce 6800 GS with 12 pipelines instead.
I know it sounds crazy, however they have 12/16 the pipelines but they are clocked 16/12ths higher to compensate for it (compared to the GeForce 6800 GT).
Recently got a Gigabyte GeForce 6800 GS, and for the price it performs far better than the GeForce 6800 XT (which lacks a 100% chance of unlocking extra pipelines, and if so you may need to underclock the 6800 XT GPU to get it stable if you can).
http://www.gigabyte.com.tw/Products/VGA/Products_Overview.aspx?ProductID=1297
The cooling solution on the Gigabyte 6800 GS is well attached, Video RAM timings are not going to cause issues down the track if the card 'heats up a little' from dust build up / age,
and they currently ship with Quake 4, and likely Power DVD 6 depending on your location, are included for free.
Gigabyte also hold several patents on GPU / VPU cooling improvements over the reference designs.
Update: Almost all shipping PCI Express x16 6800 XT/GS cards can not be unlocked, The AGP varients more often can be. However they are clocked 16/12ths higher (as above) so perform identically to the original 6800 GT (a far better card than the 6800 XT)
The 6800
GS is just a cheaper re-manufacture of the 6800 GT GPU, on a smaller die size thus it clocks higher and uses less power
, typically at around 475 - 500 MHz x 12 pipelines, vs 350 - 375 MHz x 16 pipelines of the 6800
GT.... the pixel fillrate and shader performance of the 6800 GT/GS are almost identical. The prices however... well the 6800 GS is heaps cheaper and kicks the 6800
XT in the balls at a very similar price point, while including Quake 4 (and maybe PowerDVD 6) in the box to boot.
eg: (Using easier to multiply numbers): When comparing two very similar GPUs:
- One clocked at 250 MHz with 16 pipelines,
- Compared to another similar GPU clocked at 500 MHz with 8 pipelines,
They will perform very similar to each other. (In fact the 500 Mhz / 8 pipeline one will perform slightly faster).
Any questions just e-mail or PM me.