Part 3. Test results, Conclusions

Part 1. The stock cooler of VPU ATI Radeon X800XT, Arctic Cooling ATI Silencer 4, Cooler Master CoolViva, and GlacialTech NorthPole 1000

Part 2. Zalman ZM80D-HP, VF700-AlCu, and VF700-Cu

In order to test thermal efficiency of the VPU coolers under review, we have followed practically the same method principles that are used in our CPU cooler tests. The primary data used for the consequent calculation of thermal resistance is also temperature readings of the built-in thermal diode, only the thermal source is different (now it's VPU ATI X800), the base platform (MSI RX800XT Platinum-VTD256 video card), and a set of test applications.

We have also inspected thermal operating modes of video memory - we have measured the temperature on U58 (front side) and U59 (back side) memory chips with calibrated electronic thermometers, ensuring engineering accuracy of measurement with the consequent statistic analysis of the test data.

The testbed has the following configuration:

• Motherboard: Fujitsu Siemens Computers D1688
• Processor: Intel Pentium 4 3.2 GHz (Prescott, HT Technology)
• Video card: MSI RX800XT Platinum-VTD256
• OS: Microsoft Windows XP

To simulate the close to maximum VPU thermal load, we used 3DMark03 test package — Battle of Proxycon, Troll's Lair, and Mother Nature scenes in cycle (according to our readings, these scenes reflect the typical thermal load on video cards in modern games). Each VPU cooler was tested in four 60-minute stages, the environment temperature (innards of the half-open test box) was kept at 30°C. And finally, we used the RivaTuner utility to monitor the video chip temperature.

Notes
Each cooler was tested with the stock thermal interface
The diagram contains complex results

Note
Thermal resistance θ_ja is defined as the relation
θ_ja = (T_j — T_a)/P_h, where T_j is the VPU temperature, T_a is the environment temperature (it's 30°C in this case), P_h is the VPU thermal capacity (in this case it's 33 W).

Finally, at the end of this article we publish the noise measurement results (the method of testing is described in the article Noise characteristics of coolers and the noise measurement method) as well as the efficiency/noise rating of coolers.

Note: Background noise level 18 dBA

Note
The efficiency/noise ratio (ENR) is calculated as:

ENR = DM*(R_t/TC)/(NL/R_n), where

R_t — reference temperature (it corresponds to the reference thermal resistance θ_ja of the cooling system - 40°C), TC — VPU temperature with the operating cooling system, R_n — reference noise (the reference noise level is 25 dBA), NL — noise level, generated by the cooling system, DM — denominate multiplier (10).

There seems to be no need in any comments here. Let's draw the bottom line!

Conclusions

Probably the most important conclusion for today runs that highly-effective and ergonomic cooling of video cards is a tangible matter. It can be achieved in different ways (it depends on users' preferences and the sum of money), but the results will be positive and immediate.

I'd like to particularly mention GlacialTech NorthPole 1000 — this cooler demonstrates excellent efficiency. By the combination of consumer properties (balanced thermal efficiency and noise characteristics, very simple installation, and low price) it seems to us the most interesting solution for advanced cooling of middle and high end VPU ATI video cards. Arctic Cooling ATI Silencer 4 is also an excellent cooler, it successfully combines high cooling efficiency and the ergonomic noise level. The pair of new models from Zalman (VF700-AlCu and VF700-Cu) fairs quite well — these coolers are notable for excellent universality (they support almost all modern video cards) and can cool video memory in the best way. But Zalman ZM80D-HP and Cooler Master CoolViva turn out in the group of outsiders: though they are technically advanced in terms of construction, they still cannot provide decent thermal efficiency.

So, having examined our today's contenders, we decided that Arctic Cooling ATI Silencer 4 and GlacialTech NorthPole 1000 merit the Original Design award.

And Zalman ZM80D-HP, notable for its rich bundle, gets the Excellent Package award.

That's all for today.