The PowerColor X1950 Pro models with the word Extreme in the name are equipped with the Accelero X2 cooler developed by Arctic Cooling specifically for ATI Radeon X1800/X1900/X1950 cards instead of the single-slot cooler from ATI we described in an earlier review. Let’s take a closer look at this cooler.
The Arctic Cooling Accelero series is absolutely different from the Silencer series, although uses the same configuration of fan blades. The Silencer exhausts hot air through slits in the graphics card’s mounting bracket, but the Accelero drives the stream of air perpendicularly to the mainboard’s PCB. This is a queer and, in our opinion, questionable solution. The hot air from the graphics card won’t harm the mainboard much, but won’t do it any good, either. Note that the heatsink and casing of the Accelero X2 are shaped in such a way that some of the air stream goes out at the side and is blown at the graphics card’s power circuit elements.
In spite of the radical difference in the principle of operation, the Accelero heatsink can be viewed as a development of the Silencer: there is a copper base with a heatsink consisting of aluminum plates. It is also equipped with three heat pipes for a more uniform distribution of heat. Every connection in the cooler that might affect the cooling efficiency is made very carefully, so we didn’t find anything to cavil about.
The heatsink is covered with a black casing in which a 60mm Arctic Cooling fan (a max speed of 2000rpm) is installed. For comparison, the Silencer series used a 72mm fan. The fan runs on a fluid bearing that reduces noise and increases the fan lifetime. Arctic Cooling declares an MTBF of 400,000 hours, shipping its Accelero coolers with a 6-year warranty. The fan uses a 3-wire connection with a standard connector for ATI cards.
The fan is fastened in a way we’ve never seen before. In most other coolers the fan is fixed firmly, but the Accelero uses a rubber membrane the fan motor is installed on. The flexible hanger prevents vibration to pass from the fan to the cooler’s casing, thus eliminating any extra tones in the spectrum of noise it generates. Coupled with the fluid bearing, this should make the Accelero X2 a near-silent cooler. We’ll check this out soon.
The thermal interface is provided by the cooler developer, too. There are elastic 3M thermal pads between the cooler and the memory chips, and the copper sole contacts with the GPU surface through a layer of high-quality Arctic Cooling MX-1 grease. It doesn’t conduct electricity, so as not to close any contacts on the GPU wafer, and hardens in 200 hours after application, preventing evaporation or leakage that might worsen the quality of heat transfer.
According to Arctic Cooling, a layer of MX-1, once applied, can serve effectively for 8 years.
The Arctic Cooling Accelero X2 is intended to cool hottest graphics cards from ATI Technologies, so it is easy for it to cope with the not-very-hot Radeon X1950 Pro. Perhaps we’ll get better results at overclocking. Let’s check this out and see how quiet this cooling system is.