Zalman VF900 Cu
Author: Luka Rakamaric
Date: 17 Dec 2006

If you are not completely new to the IT market, you have probably heard of Zalman. They are a Korean manufacturer of aftermarket cooling solutions, and have been ruling without much opposition in the high quality CPU coolers for years now. Ever since their 7000 series, there have been no manufacturers that managed to introduce a better product in the same dimensions and noise level. Today we will take a look at their VF900 Cu heatsink, which is designed to cool down today?s most powerful GPUs.
The VF900 is an improved version of the VF700 model, which was their first active GPU cooler. Like almost all new products in the cooling department, it features two heatpipes, which use phase change to transport heat away from the chips. A special liquid similar to alcohol is evaporated at the heat source and then travels through the pipe to the other end where it turns into a liquid again. This process eficiently transfers heat to the copper fins, arranged in a very characteristic Zalman flower to which the heatpipes are connected.
The package contains everything you will need to mount the cooler on various cards. There are 5 hole sets to chose from, but most of the new cards use the largest hole distance. Also included are eight passive memory heatsinks. They have a thermal conducting adhesive already on, so you only need to put one on each memory chip. We can?t call these heatsinks passive, since the VF900 blows directly at them, giving them an active component.
There is also a well known Zalman accessory, the FanMate 2, which serves as a RPM control for the fan. The fan itself connects to the 3 pin motherboard connector, and not the graphics card 2 pin. We installed the VF900-CU LED on the 7900GT from NVIDIA, which operates at 450 MHz. Using a stock cooler, which does not cool memory, we managed to get the GPU to 553 MHz before we started seeing artifacts in stress tests. Memory was able to go from 1320 MHz to 1450 MHz without the heatsinks. We tried the same thing with Sapphire's X850XT (one of our least favourite cooling solution ever), and got pretty much the same results.
Using the Zalman cooler, we achieved the following results. Anything more would require a voltmod of the card, which we feel that most users don?t want to get themselves into. However we can see that the load temperature is only 51 degrees Celsius, which leaves a lot of room for even more heat.