When you are using 2D Windows the card is completely inaudible, the fan runs extremely slow. Once temperature rises, the fan speed will slowly increase. One problem with the fan speed is that it gets quite loud once the GPU reaches 80°C which is not too uncommon with this card. Here the fan speed makes a jump, which is clearly audible. Also the fan is no longer silent now.
The problem now becomes that once the fan is running fast the temperature will drop down to a point where the fan can go slower. This results in repetitive jumps in fan speed as following illustration shows (obtained with ATITool stress test).
Such high temperatures are only reached while very demanding games are running. In our benchmark suite this fan speed was only reached during some 3DMark tests. The same is happening on the X1900 of course, but here the difference is not that big, so you notice it less.
The easiest way to avoid this is to optimize your case airflow in a way that the GPU temperature does not go over 80°C.
Overall the fan of the X1950 feels considerably quieter than the X1900. This is not only because the fan noise is reduced, the noise has a different quality which sounds not so annoying.
Power consumptionTo measure power consumption the whole system's mains power draw was measured. This means that these numbers include CPU, Memory, HDD, Video card, PSU inefficiency. To get a rough idea how much power these cards actually consume a Radeon 9000 PCI was thrown into the mix which barely consumes any power.
Idle means Windows sitting at the desktop (1600x1200). Load means peak power consumption during 3DMark05 at 1600x1200 6xAA, 16xAF.
As promised by ATI, power consumption is down a bit. It's not much, but every little bit helps. Since the total heat output is lower, the overclocking potential should be increased.