CrossFire: Physical Parameters
Noise: in the Footsteps of GeForce FX 5800 Ultra
As we have already said, the dual-slot reference cooling system from ATI operates really quietly only at the lowest fan rotation speeds. At higher rotation speeds the fan produces pretty loud noise. And since the cooling system casing is a good resonator, the noise acquires pretty unpleasant “plastic” shade, which turns out very irritating, especially during long term work with the system at this fan rotation speed. In regular work mode the cooler of RADEON X850 XT/XT Platinum Edition works at minimum fan rotation speed most of the time, so that the generated noise stays within reasonable range. It only speeds up during long work in 3D mode. CrossFire system acts differently: the master card fan rotated at very high speed throughout the entire test session, however, the worst thing about it was the constantly changing rotation speed, so that the noise produced by the system turned out simply unbearable. The only solution with a more unpleasant noise produced by the cooling system was XGI Volari Duo V8 Ultra. If you remember, we reported that its two high-speed fans generated high-frequency squealing noise (for details see our article called Club3D Volari Duo V8 Ultra Review: XGI Volari Family Coming to Graphics Market).
However, CrossFire cooling solutions does have one potentially great advantage: two graphics cards that suck the system air inside the PC case and then oust it outside the system should have a great positive effect on the internal system thermal conditions. I said “potentially great”, because you will hardly put up with the generated noise for the sake of better system cooling.
Of course, you should keep in mind that our test session was performed in an open test stand. However, if the mass CrossFire systems will act the same way as we have just described above, you will have to give up comfortable gaming experience once and for all.
Since it is right now impossible to overclock the CrossFire kit, we tested the overclocking potential of the graphics accelerators from this kit separately. Our tests revealed the following results:
- RADEON X850 XT CrossFire Edition: 610/640 (1280) MHz.
- RADEON X850 XT: 590/630 (1260) MHz.
The graphics cards worked stably at these frequencies. They received additional cooling from the 120-mm fan installed behind both cards. I have to say that 610MHz is a record for RADEON X850 XT in our labs. All our previous attempts to overclock the members of this graphics card family ended around 560MHz-580MHz.