Board analysis

If you’re familiar with the board design of NVIDIA’s GeForce 6800 GPUs, you’ll quickly recognize quite a few differences between the GeForce 6800 GS and its direct predecessor, the GeForce 6800. In fact, the boards have practically nothing in common. But it doesn’t stop there, as the GeForce 6800 GS doesn’t even follow the GeForce 6800 GT’s board design.

Instead, the GeForce 6800 GS reference board supplied to us by NVIDIA is a 100% replica of the GeForce 7800 GT’s reference board design, right down to the component placement and the use of both polymer and electrolytic capacitors. The only difference lies in the cooler used on the two cards.


In laymen’s terms, what this basically means is that NVIDIA has basically taken the GeForce 6800 GS GPU and slapped it onto a GeForce 7800 GT PCB. We were absolutely floored when we first saw this! Of course, with dramatically higher clocks than its predecessor, the move to the new board design was a requirement for the GeForce 6800 GS, we just didn’t expect NVIDIA to be so aggressive on a mainstream board.

Overclockers are going to love this.



This PCB has been built from the ground up for high clocks. It is after all, not uncommon to find GeForce 7800 GTs running overclocked right around 490MHz-500MHz on stock cooling. As a result, this means that the GeForce 6800 GS is longer than both the GeForce 6800 and 6800 GT (although it’s not much in the case of the 6800 GT), making it a little less than ideal for some small form factor (SFF) boxes, but we have a feeling SFF users intrigued by the 6800 GS will find a way to make it work in their system. According to NVIDIA, the GeForce 6800 GS draws up to 70W of power, so a 350-watt PSU is recommended for single card setups, while a 420W PSU is recommended for SLI.

The cooling unit used on the GeForce 6800 GS is like nothing we’ve ever seen on an NVIDIA reference board. While at first glance it resembles the GeForce 6800 GT heatsink/fan unit, taking a closer look reveals that NVIDIA has employed a copper/aluminum combination for the GeForce 6800 GS’ cooling. This marks the first time NVIDIA has used copper on a reference board since the GeForce FX 5800 Ultra.

The GPU itself is cooled by a copper heatsink. When combined with the board’s fan, the copper heatsink does a very good job of keeping the graphics core cool. In all honesty, this is probably a bit of overkill for a 12-pipe 110-nm GPU, even if it is running at 425MHz. We noted core temperatures never topped 55 degrees Celsius, further reinforcing this. (Again, this is all the more reason why we’re so impressed with the GeForce 6800 GS’ board design.)


To help keep the memory cool, NVIDIA then employs a separate aluminum heatsink. This heatsink, as well as the aluminum heatpipe and blower-style fan, are all borrowed completely from the reference design cooler used on the GeForce 6800 GT.

It will be interesting to see how closely NVIDIA’s board partners follow the GeForce 6800 GS reference design. We don’t think anyone would make any changes to the basic board design and its use of the 7800 GT PCB, after all the move does have the added benefit of helping to simplify production (as multiple card lines will be based on one PCB), but we will be curious to see how many of NVIDIA’s board partners integrate the copper cooling on their retail GeForce 6800 GS cards. We wouldn’t be surprised to see more than one board partner take the easy way out and simply take the aluminum GeForce 6800 GT cooler and use it on their GeForce 6800 GS board.