|Zalman VF3000A VGA Cooler|
|Reviews - Featured Reviews: Cooling|
|Written by Bruce Normann|
|Friday, 10 September 2010|
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ZALMAN VF3000A Installation
The installation process went smoothly, with the exception of areas on my second-generation board that were not compatible with the supplied heatsink; namely the VRM section. The differences between the reference design and the later boards designed by the AIB partners is significant. The interface of the main heatsink and fan to the GPU was perfect, as that is an area that has been constant on every Radeon HD 58xx series board since day one. It's important to realize that this cooler is designed specifically for the first generation Radeon HD 5870 and HD 5850 video cards. It also works on HD 5830 cards, but most of them are patterned after second generation designs, so you may lose some functionality. This is completely explained in the installation instructions.
You can see from this view how open the entire assembly is, after it's all put together. There is a lot of exposed area on the board, which means all of the smaller devices have a bit more room to breathe, and they all probably run just a bit cooler as a result. This is a marked contrast to the reference card which is closed up tighter than a drum; well more like a rectangular pipe, I suppose. The color scheme is obviously all red, all the time. I had a choice of 5870 boards to install the VF3000A cooler on, and this one was the clear favorite. The cooler looks like it's shifted towards the top more than it actually is, due to the height factor, which we'll look at more closely now.
From the side, you can see the amount of vertical space between the cooler and the card. It's a tight packaging job to fit those five 6mm heatpipes in there, each with a u-turn so that it can run the full length of the cooler. Many other designs do that U-turn in the horizontal dimension, or as close to it as possible, to minimize the height penalty. Those coolers give up some heat transfer capability between the heatpipe and the fins, though. The VF3000 has approximately 11,200 square millimeters of contact area between the heatpipes and the aluminum fins. The PowerColor unit, which is no slouch in the cooling department as we'll see later, only has about 7920 mm2 of contact area. But, we all should recognize by now that one number or one design feature does not automatically define cooling performance. It's a balance of factors, some of which you can't even see!
From the top side, it's easier to see the clearance between the various heatsinks on the memory chips and Power MOSFETs and the main set of cooling fins. It may look like a lot, but I had to buy special low-profile heatsinks for the MOSFETs, which are just 9mm tall. The standard type is 14mm tall, and they wouldn't clear the lower part of the VF3000A fin assembly. You can also see the space taken up by the thickness of the fans, which are both 15mm wide and 92mm in the other two directions.
I've spent a fair amount of time detailing the reasons why the Zalman VF3000A is taller than a typical dual-slot cooler, and in this view you can see by how much. It's at least two and a half slots wide, but not quite a full three slots. Given the amount of heat these high-end GPUs produce, the size of the fans needed to cool them, and the massive amount of surface area consumed by the aluminum cooling fins, it should be pretty obvious from this view how silly it is to try and pump all that heat through those eleven small slots. You can read more about this folly in my Final Thoughts.
For those who absolutely need to know exactly how tall this cooler is, here's the image for you. By my reckoning, it sits just about 50mm above the surface of the board it's mounted to. That's about 15mm taller than a normal two-slot cooler, which usually tops out at 35mm higher than the board. For me, the additional height is a complete non-issue, but I understand that for others it is most definitely a problem. The arrangement of expansion slots on your motherboard is not something you have a lot of say over, especially if you already own the board. Sometimes you can move cards to another open slot, but with the mix of PCI, PCI-Express and the 1x, 4x, 8x, and 16x versions of PCI-E, sometimes there's only one way to position the boards you've got.
Well, we've put in all this work examining the Zalman VF3000A, and assembling it. Now it's time to test it. We'll start the next section by describing our test methodology, and then examine the results.