The title of this article might sound like a contradiction in terms to you, most people probably wouldn't use sizzling hot and Canada in the same sentence, but this time around I'm not talking about the weather or climate up North. What I am referring to is ATIís latest PCI-E graphic card which was introduced a few days ago. Dubbed the X850XT PE it is ATI's new, PCI-E only, top-end graphic card that replaces the X800XT PE, which never really saw much availability in the retail market anyway. Basically the X850XT PE is ATIís fall refresh part and besides a minor increase in graphic processor and memory clockspeed it doesnít offer much in terms of new features. Besides the X850 series ATI also launched a whole range of PCI-E graphic cards based on the new R423 graphics processor, which makes ATIís top-end line-up rather confusing. As of today we have the option of choosing between a X800, X800 SE, X800XT, X800XT PE, X800 XL, X850 Pro, X850 XT and X850XT PE, to complicate matters further some of these cards are also available in AGP.
The R480 graphics processor as found on the X850 series graphic cards.
What is new with the X850XT PE and the other cards in the X850 series is that ATI has gone back to the drawing board and has taken a good hard look at power consumption and heat production. Theyíve made modifications to the design, which they unfortunately did not want to comment on in detail, that encompass new thermal management features on the R480 graphic processor to shut parts of the graphic processor off when not in use. This obviously makes sense, as who needs a graphic card running at full steam when youíre not using any of the 3D features but are simply working in 2D? This not only cuts into the power consumption of the X850 series cards, but also reduces their idle temperatures and overall heat production.
The cooling solution as found on the XT850XT PE, utilizing a radial fan.
To further optimize the design ATI has also implemented a thermal throttling feature that will reduce the clockspeed of the graphic processor dynamically when things get too hot. We doubt whether thatís going to happen anytime soon as with the X850XT PE ATI has also introduced their first foray into cooling solutions that span the width of two PCI slots. Yes, youíve read that correctly, ATI will be using a dual-slot cooling solution on itís X850XT PE part, but the X850XT will also be outfitted with one weíre told. The cooling solution uses a ducted fan that pulls air from inside the case over the skived copper heatsink that sits on the graphic processor outside of the case through the PCI slot bracket. Weíve seen similar solutions from 3rd party manufacturers such as Artic Cooling, that offer significant benefits over the stock cooling solution mounted on ATIís Radeon X-series and NVIDIAís GeForce 6-series graphic cards.
The dual slot bracket with a grill used to exhaust hot air outside.
ATIís attempt at making a cooling solution similar to these has, in our opinion, however fallen short on a few accounts. Firstly the fan is audible over the other fans running in our test system when the graphic card is idling and clearly spins up to a high rpm when taxed to the fullest. Weíve seen this happening when mounting the X850XT PE inside a typical mid tower case, with adequate airflow, and case side-panels mounted. Secondly the graphic card produces a substantial amount of heat, more so than any other graphic card weíve tested to date. Although part of that heat is dumped outside of the case the backside of the card, which holds four of a total of eight GDDR3 memory chips, cooled by an aluminum strip, get blistering hot as well. This heat is dumped inside the case and thus helps to raise the case temperature. We measured a case temperature of around 40 degrees Celsius with the X850XT PE, versus just touching upon 35 degrees with a Radeon X800XT.
The skived fin copper heatsink which helps the graphics processor keep cool.
Overall the cooling solution managed to keep the graphic card running without any thermal problems though. And to be honest the noise production we mentioned could be a non-issue to some users, which have multiple case fans and a high-power fan on their processor, that will make it hard to single out the noise produced by the X850XT PE. In our experience, from having recently evaluated
the Arctic Cooling heatsinks, it is however possible to keep even a high-end card running cool. It is unfortunate that stock heatsinks have yet to reach the level of performance and noise production that is offered by them, as the cost, $30, is only a fraction of the price the X850XT PE will be retailing for. From our perspective thatís a small investment to make on part of the manufacturer and certainly of benefit to the consumer. Weíll have to see whether ATI board partners will opt for such a solution as some have with their X800 products. For example Sapphire has been offering an X800 Pro outfitted with an Arctic Cooling heatsink for quite some time now.
As for performance we donít have many complaints, on our Pentium 4 3.46GHz EE testbed featuring the Intel 925XE chipset and 1GB of memory the X850XT PE manages to outclass the previous ATI flagship, the X800XT PE, but not by a significant margin. The clockspeed difference of 20MHz on both the graphic processor and the memory gives the X850XT PE the performance edge, but it isnít exactly mind boggling. When looking at our benchmarks it is clear that when running at stock speeds the X850XT PE and X800XT PE come within a few percent of each other and when clocked at the same speed, using Entechís PowerStrip, we could not distinguish one card from the other.
So as not to bore you with pages filled with graphs that show a X850XT PE slightly besting the X800XT PE in all benchmarks we think it is suffice to say that the X850XT PE is the fastest graphic card currently available for PCI-E, whilst the X800XT PE still holds the performance crown for AGP. Only in Doom3 NVIDIA's GeForce 6800GT and 6800 Ultra manage to best both ATI graphics cards. Letís just hope that the X850XT PE doesnít turn out to be a phantom edition like the X800XT PE was and we see actual availability for those who can afford it.