Zalman VF700-Cu review

You only need to take a look at p42 to see that, unlike CPU manufacturers, the designers of graphics processing units haven't yet got round to concentrating on reducing the power consumption of their top-end products. The result is massively power-hungry chips that need loud, over-the-top cooling.

The VF700-Cu graphics cooler adapts Zalman's 'flower cooler' design used to exceptional effect with its CNPS7000 range of CPU heatsinks, in combination with a large low-rev fan for minimum noise. The company makes heady claims for the VF700-Cu. Designed for cards from the ATi 9700 and nVidia 5700 series onwards, Zalman declares it effective enough for the whole ATi X800 range (including the X850) and the whole nVidia GeForce 6000 series too. It doesn't fit nVidia PCX-series PCI-Express cards though, and the height of the heatsink means you'll also lose the use of the adjacent PCI slot.

Changing your graphics card cooler is a more involved process than installing a new CPU heatsink. And you're highly likely to void your card's warranty by doing so. But the process is by no means nuclear physics: we managed to remove the old heatsink from our test card - an ATi 9800 XT - and fit the VF700-Cu in about 20 minutes. Removing the existing heatsink only required undoing a couple of screws and disconnecting the fan's power cable, after which it dropped off with no problem.

Most stock graphics coolers extend across the onboard RAM chips too, whereas the VF700-Cu is only in direct contact with the GPU itself. To cool the RAM, the kit comes with a set of discrete heatsinks, preloaded with adhesive thermal transfer tape.

Installation of the main heatsink is more involved, but if you can assemble an IKEA desk you can assemble this. The holes at either side of the GPU left by the stock heatsink take a couple of screw adaptors on the front and rear sides of the board. At the rear, these attach to a diagonal brace. At the front, you need to apply some of the supplied thermal paste, then offer up the heatsink itself and screw in the spring-loaded central bar, a few turns at a time to prevent uneven pressure on the board.

Rather than being reattached to an onboard power connector, the cooling fan needs to be connected to a spare 12V Molex connector; a little messy but not surprising, since fan connectors on graphics cards are non-standard. However, the clutter is increased by the generic power-adaptor cable, which has one Molex connector and a total of four power connectors on the graphics card end. Two of these supply 5V and two provide 12V. If you want the quietest operation, attach it to one of the 5V connectors; for more effective cooling, use a 12V line. It's nice to have the choice, but we'd have preferred a neater method of speed control without redundant connectors.

In 5V mode, the fan was just still audible - we'd put its output a little higher than the claimed 18dBA - but you'll only hear it if the rest of your system is virtually silent. No amount of bashing our 9800 XT card in Far Cry or Half-Life 2 could make it overheat either. We're confident the latest cards will present no problem if you put the fan into the acceptably quiet 12V mode. The question is whether you're prepared to void the warranty on your £350 current-generation graphics card. If you are, the Zalman will make your life much quieter.

Author: David Fearon