|ASUS GeForce GTX 285 Matrix Video Card|
|Reviews - Featured Reviews: Video Cards|
|Written by Bruce Normann - Edited by Olin Coles|
|Sunday, 06 September 2009|
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Closer Look: GTX285 MATRIX
Cooling is one of the most obvious upgrades for a video card. The single blower wheel at the front of the card doesn't look very impressive, compared to some of the dual and triple fan designs that have been on offer for a while now. It's what's hidden behind the shroud that makes the cooling solution of the ASUS GTX285 MATRIX special. The Extreme Cooler starts with a noticeable trio of 8mm diameter heat pipes mounted on a big copper block, that transfer the heat away from the large top surface of the GTX285 chip package. Later, we'll see there's something more hidden under the surface of this cooler. Through the pipes, heat gets sent to a big, chunky set of aluminum fins, and then out the back of the card as warm air.
ASUS gets high marks for designing a non-reference cooler that exhausts almost all the heat out the back of the case. All of the dual-fan designs I've seen so far, recycle 90 percent of the GPU heat back into the interior of the case. As much as I appreciate their ability to keep the GPU cool, I don't want all that heat migrating up to the Northbridge and CPU. The GTX285 MATRIX is definitely a dual-slot device, as this image shows. The double-width adapter plate at the rear is slotted to allow the heat to escape from the case. During stress testing, the stream of warm air exiting through these slots was significant, proving the capability of the Extreme Cooler to pull heat away from the GPU and move it outside the case.
The cooling system looks fairly straightforward, with three large, copper pipes coming out of the GPU block and angling their way over to three grooves punched into the fin assembly. The three pipes are soldered to the fins, across their whole width. If you look closely, you can see there are two additional heatpipes that are flattened and nearly hidden below the fin assembly. The net effect, besides the obvious one of adding two more heatpipes, is that the heat flows from the pipes into the fins from two, opposing directions. It's a clever design that I almost missed, until I started counting pipes at the GPU end.
The copper block that contacts the GPU surface is fairly thin; it's really more of a heat spreader than a heat sink. Its real job is to get the heat passed through it and into the heatpipes. The surface is polished to a dull finish and it's flat enough for the purpose. It's a bit over size, more for the benefit of contact with the heat pipes, than for the GPU. The memory, MOSFETs, and RAMDAC all contact the cast aluminum frame, via plastic thermal interface tape. Judging by the deep imprints the chips left when I disassembled the unit, there's plenty of pressure applied to these components, compressing the thermal tape by over 50%. This tape was different from most of the others I've seen, it had a slick polymer film on the side contacting the devices, so there is no chance of pulling the tape apart during disassembly of the card. I took the card apart after several days of stress testing, and there was no sign of sticking. So, if you want to experiment with different thermal paste on the GPU, there's no worry about damaging the thermal tape. This is just one (hidden) example of the thought that went into producing a true enthusiast product.
Once the GTX285 MATRIX is installed and operating, it's impossible to miss the prominent display for the Real-Time Hardware Loading Monitor. It changes color (Green, Blue-Green, Dark Blue, Purple, Red) based on how hard the card is loaded. FWIW, with stock clock settings, I only got it to turn red using the FurMark stress test; no gaming benchmark got past purple. With a major overclock and voltage increases for the GPU and memory, some games turned the MATRIX red.
Power requirements are supplied by two auxiliary PCI-E connectors, one of the 8 pin variety, and one 6 pin. Modern power supplies have convertible plugs that can handle either version. Most of the NVIDIA GT200 series cards use two 6 pin connectors, but more pins are always better, and the power supply spec supports them, so why not use them? The card uses the full 10.5" of allowed length, so the connectors are along the upper edge, which is generally convenient for cable access. Next to the power connectors is the S/PDIF connector for your HDMI interface needs.
Let's dig a little deeper into the details of this impressive piece of hardware, in the next section.