X-bit labs

ATI RADEON X800 XL 512MB Graphics Card Review. 512MB: Today’s Need or Reserve for the Future? (page 4)

Category: Video

by Alexey Stepin , Anton Shilov

[ 05/05/2005 | 02:10 PM ]

Closer Look: Cooling System

The cooling system of this graphics card deserves a separate mention in our review. It is very much different from the reference cooler you can see on the regular RADEON X800 XL based graphics cards with 256MB of onboard memory. We have already seen something like that by PowerColor X800 XL graphics card (for details see our article called PowerColor X850 XT and PowerColor X800XL Graphics Cards Review). However, the similarity you might see is mostly first glance observation, although both coolers use a pretty noisy ADDA AD4512HB-E03 fan powered by 0.35A current.

The new cooler features a solid copper footing providing tight contact with the VPU surface, while the PowerColor X800 XL features an aluminum heatsink footing.

If you take a closer look at the card, you will also see that there ate two flat heatpipes transferring the heat from the footing above the VPU and distributing it evenly all over the heatsink composed of thin aluminum ribs. The memory located on the front side of the PCB is cooled down with the same heatsink as the VPU, as the footing features special bumps covering the memory chips, too. On the back of the PCB there is an aluminum plate dissipating the heat from memory chips located there. It is not a very efficient cooling solution, however, GDDR3 memory working at about 500MHz (1000MHz) frequency generates not that much heat, so the existing cooling appears more than enough.

The cooler is fastened to the PCB with four screws, three of which also hold in place the above mentioned aluminum plate. Two more screws press a special bracket to the bottom side of the PCB. This bracket is intended to prevent the PCB from curving and also serves as an additional cooler retention. The thermal interface is provided by two types of thermal paste: thick gray paste for the VPU and white silicon paste for the memory chips.

The entire construction leaves very good impression of a well-done thoughtful solution, although the fan still aroused a few concerns: according to our PowerColor X800 XL tests, it becomes very noisy at its maximum rotation speed. Everything depends on the rotation speed regulation circuit, and if the fan will be working at lower rotation speed most of the time, the card can be really quiet. In the next chapter of our review we will specifically dwell on this matter.