PerformanceTo test the cooling performance of the cooler I let 3DMark 06 loop until the whole system had heated up. All the temperatures were recorded with RivaTuner and the fan adjustments were all made from RivaTuner as well. In order to test how this cooler performs I ran 3DMark06 for an hour and then made a bench round where I recorded the peak temperature of the card. I used RivaTuner 2.08 to get the data needed for the review due to various improvements over the older versions used in the previous cooler reviews. And since nothing on the temperature monitoring front has changed in the program all results are still valid compared to the old ones. I even did a test run to see if the temperatures matched the ones obtained with version 2.02 and they were spot on. The tests were all ran with an ambient temperature of 20 degrees.
The Arctic Cooling Accelero Xtreme will be facing some very tough competition from both Zalman and Thermalright. The Thermalright HR-03 Plus which I reviewed not that long ago sets the benchmark for cooling performance.
When it comes to cooling the PCB of the card, the Accelero Xtreme falls a bit behind the competition. In my opinion the few degrees difference should not mean the difference between a stable or unstable card. As long as the temperatures are within the acceptable values I see no downside to the PCB running a few degrees hotter.
The GPU is kept really cool by this cooler. I repeated the tests several times to confirm the results because I thought they were a bit too good to be true. It turned out that there weren't any irregularities. This cooler just has an amazing potential when it comes to keeping a card cool even with a limited airflow. Of course the GeForce 8800 GTS 320 MB is not the hottest card out there, but still the GPU temperatures are really good, almost on par with the massive Thermalright HR-03. Under load the Accelero Xtreme is way ahead of both the stock cooler at max. fan speed and the Zalman VF1000. Considering that the Accelero is about one third of the height of the HR-03, the cooling capability of the cooler is enormous.
NoiseThe Arctic Cooling Accelero Xtreme can be anywhere from inaudible to semi loud depending on what fan duty cycle you set it to. Per default the fan duty cycle is 60% on my 8800 GTS and that makes the cooler barely audible over my 120 mm case fans running on 7V. Turning the duty cycle below 50% and it is completely inaudible over the other fans in my system. I tried stopping all fans in my system just to see how much noise the cooler makes on its own and to my surprise it is extremely quiet at low fan speeds. In my fairly low noise system I am quite satisfied with noise levels from the card with the duty cycle set to 60%.
40% fan duty cycle equals about 950 RPMs making the cooler dead silent, absolutely no buzzing or humming. 60% fan duty cycle makes the fans spin around at approximately 1450 RPMs making the cooler noisier, but no weird humming or buzzing. 80% takes the fan speed to about 1850 RPMs making each of the three fans produce a fair amount of noise, no excessive wind noise.
At 100% fan speed I do not like to be near the PC, the three fans are doing about 2200 RPMs and make too much noise for my liking.
The best thing about this cooler besides the shape and the design of the heat pipes is the fact that you can trim the speed of the fans without making them hum or buzz. This is largely due to the fact that they are PWM controlled.