|Zalman VF900-Cu Ultra Quiet Heatpipe VGA Cooler|
|Reviews - Featured Reviews: Cooling|
|Written by Bruce Normann - Edited by Olin Coles|
|Wednesday, 18 June 2008|
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Testing & Results
My testing revolved around the two core performance characteristics of any cooler, the temperature of the semiconductor device and any noise that the cooler makes. After trying out the VF-900 Cu on the original GeForce 7300GT, I realized that I needed to push the cooler a little more and did all my testing on a brand new eVGA Geforce 8600GT card. This GPU is the least expensive nVIDIA model that can realistically be used for light gaming. If you play more than once a month, the minimum would be an 8800GT.
I measured the idle and load temperatures with the on-chip sensor, as reported by CPUID Hardware Monitor. I also used this program to get ambient temps for reference. Under idle conditions, the South Bridge sensor on this motherboard gives a very good reading of the ambient temperature inside the case. I know this isn't true for everyone, but in my case it is, very consistent and is easily monitored via software.
The load for the GPU was provided by two 3D benchmarking utilities:
In each case, screen resolutions were set to 1280x1024, and the tests were looped a minimum of 5 times to ensure that the maximum temperature had been reached. Individual tests were run to verify that no temperature increases occurred after 3 successive loops. In the case of the 3dMark06 test, the SM2.0 Graphics Tests and the HDR/SM3.0 Graphics Tests were the only two sets of tests run, so as not to give the GPU chip any break during other tests that primarily load up the CPU. I ran the final tests only after giving the thermal interface material plenty of time to settle in. The Tuniq TX-2 is not known for needing any specific cure time, but I did notice better idle temps after 2-3 days of hard running.
The noise factor turned out to be a go-no go test. My goal was for the cooler to be inaudible, as the rest of the PC was already meeting that standard, when placed on the floor at my feet.
The fruits of all this labor: a cooler and MUCH quieter PC. The temp reductions at both idle and full load are significant:
With the minimal temperature differences between low fan speed and high when the chip is under load, it's clear the Zalman VF900-Cu has plenty of headroom left when dealing with a nVIDIA 8600GT. It would be interesting to see how well it could do on a 8800GT or ATI 3870. This is excellent thermal performance, load temps are basically cut in HALF!
The noise performance was outstanding. In only one situation could I ever hear the fan, with the FAN MATE 2 set on High and the side door completely off the case. With the side door on, or if the fan was set on Low, it was completely inaudible. What a nice difference, and completely fitting with Zalman's product origins, "Noiseless Computing".