Graphic card manufacturers are more or less caught in a dilemma, their graphic processors generate about the same amount of heat as a desktop processor yet they have to work within the room available between two PCI slots. NVIDIA was actually the first to break the mold and introduce a heatsink on their GeForce FX series cards that occupied two slots. Unfortunately the heatsink was rather loud due to a number of design problems with the axial fan and the casing, but the idea caught on and many manufacturers of aftermarket heatsinks followed suit.
The Zalman ZM80D-HP heatpipe heatsink with additional ZM-OP1 fan mounted.
Zalman is one of those manufacturers that, for a long time, has been offering a heatsink utilizing heatpipes
to draw the heat away from the hot graphics processor. Initially this heatsink was meant to offer passive cooling in well ventilated cases, which it did quite well, even on cards such as ATIís Radeon 9800 Pro. Modern graphic cards however, such as NVIDIAís GeForce 6 series, or ATIís X800 series generate substantially more heat than their predecessors. To suit the needs of these graphic cards Zalman has beefed up the performance of their heatsink, equipping it with an 80x80mm fan and a more efficient heatsink design. Their heatsink is suitable for both ATI and NVIDIA graphics cards, by aligning the base plate differently to the heatpipes, a simple one-size-fits-all design so to speak.
The Arctic Cooling ATI Silencer 1 mounted on the Radeon 9800 Pro.
Another manufacturer that offers a whole range of graphic card heatsinks all tailored to fit a specific category of graphic cards is Arctic Cooling. Whatís remarkable about these heatsinks is that they all feature a copper base heatsink with aluminum fins that is cooled by a whisper quiet, even at full rpm, 72 mm fan. The design is remarkable because it is the only aftermarket solution that tackles two problems in one fell swoop. The fan sucks air in from inside the case, across the heatsink and vents it outside of the case through a custom case bracket. By doing this it not only gets rid of the heat generated by the graphic card, but also lowers the case temperature as the heat from the graphics card is dumped outside of the case.
The Arctic Cooling heatsink pictured with a motherboard, you'll loose the first PCI-slot.
So we have two heatsinks here which both use a different approach, Zalman has a design that will fit the majority of graphics cards without the need to offer different models, Arctic Cooling has different designs for different graphics cards, but since most graphic card manufacturers use the reference design from ATI or NVIDIA they have no more than a handful of heatsinks that fit 99% of all graphic cards. Weíve put both heatsinks to the test by mounting them onto a ATI Radeon X800XT PE and recording temperatures. To get a real-world test scenario weíve put the graphic card into an actual system and measured temperatures of the card and the case temperature with the case closed, when idling and under full load. Below youíll find the results of both the Zalman ZM80D-HP with the ZM-OP1 fan, and the Arctic Cooling ATI Silencer 4. The pictures you see with the article are from mounting the heatsinks to an ATI Radeon 9800 Pro.
The Zalman heatsink pictured with a motherboard, again you loose the first PCI-slot.
As is evident from the temperatures recorded the Arctic Cooling heatsinks offer far better performance than the Zalman, not only by keeping the graphic cards several degrees cooler than the Zalman, but also by lowering the case temperature. Thereís a catch however, the Zalman can be operated without the fan, if thereís enough airflow inside a case; the Arctic Cooling heatsinks rely on their fans to keep things cool. To be honest we would not recommend using the Zalman without a fan for anything faster than a Radeon 9800 Pro or GeForce FX5700, as even with these cards the heatsink is too hot to touch. Another advantage of the Arctic Cooling heatsink is that the fans connects directly to the graphic card, making full use of fan throttling on newer graphics cards, thus further reducing the noise level, the Zalman ZM-OP1 fan does not have this feature.
The modification to the Zalman connector to enable 7-volts on the fan.
As for noise production either solution performs admirably, with the Arctic Cooling heatsinks generating the best results, having a noise level which is below that of the quietest harddisks or power supplies. With a Radeon X800 Pro, which has fan throttling, the Arctic Cooling heatsink is not audible when the card is idling unless you put your ear right up to the exhaust bracket on your case. The Zalman ZM-OP1 fan has two, user selectable, settings which operate the fan at either 5- or 12-volts. We wouldíve welcomed a 7-volts setting (5-12 = 7-volts) as the fan set at 5-volts was unable to cool the Radeon X800 Pro down to safe levels under full load, the 12-volt setting was too loud to be really feasible. As seen from the picture above it is however easy to modify the Zalman ZM-OP1 to operate at 7-volts, this provides enough cooling, whilst keeping things quiet.
To summarize our findings it will come as no surprise to you that the Arctic Cooling heatsinks come highly recommended; due to the innovative design, the easy installation but more so the performance, noise levels and the fact that it is covered by a 6-year warranty. Zalmanís ZM80D-HP isnít a bad product, but suffers from the fact that it is not designed to handle modern graphic cards without the aid of an extra fan and is a bit of a hassle to install. The other downside, in comparison to the Arctic Cooling heatsinks, is that it dumps all of the heat inside of the case instead of venting it outside. If you however need to cool a mid-range or entry-level graphics card and donít want any fan noise whatsoever, then look no further.