Noise and Overclocking
We measured the level of noise produced by the cooling system installed on the PowerColor X1950 Pro Extreme with a digital sound-level meter Velleman DVM1326 (0.1dB resolution) using A-curve weighing. At the time of our tests the level of ambient noise in our lab was 36dBA and the level of noise at a distance of 1 meter from a working testbed with a passively cooled graphics card inside was 40dBA. We got the following results:
The PowerColor X1950 Pro Extreme is somewhat better than the reference Radeon X1950 Pro in its noise characteristics. Basing on the readings of the sound-level meter, we might say that the graphics cards produce the same noise as it’s impossible to catch such a small difference by ear. But besides the numbers in decibel, there are certain nuances you can indeed catch without any tools. The noise spectrum of the Accelero X2 doesn’t have any plastic tone caused by the resonating casing because the fan is fastened through a vibration-damping membrane. The fan is always rotating at 2000rpm, so the PowerColor X1950 Pro Extreme produces the same noise all the time. Although the card is not exactly silent, it may be considered as such because its noise isn’t audible against the noise from other system components like hard drives, CPU cooler, and system/PSU fans.
Alas, the PowerColor X1950 Pro failed in our overclockability tests in spite of the advanced cooling system. The core of our card, which is pre-overclocked by the manufacture, showed some frequency growth like 15-20MHz at first, but began to display image artifacts after a while and we had to roll back to 595MHz. The memory refused to get overclocked at all. There were flickering bands and other signs of over-overclocking after we had tried to increased its frequency even by 5MHz.
Perhaps there was poor contact between the cooler’s sole and the GPU die, but we think the real reason was zero overclockability of our sample of the PowerColor X1950 Pro Extreme. You may be luckier with another sample of the same graphics card model. Since we didn’t achieve a tangible growth of GPU and memory frequencies, we decided to benchmark our PowerColor X1950 Pro Extreme 256MB only at its default clock rates of 595/700 (1400) MHz.