Heat shield and desk fan in hand, Bennett Ring sees what happens when Peltiers turn bad.
You know extreme cooling is no longer quite as extreme when the likes of Thermaltake start pumping out mass-produced versions that even a chimp would be comfortable installing. We saw it with water cooling in the Aquarius II kit from Thermaltake, and now we’re seeing it with Peltier coolers. The SubZero 4G is Thermaltake’s quick and easy fix for those of you who are thinking of delving into the world of thermoelectric cooling, promising a 90-second installation and the same performance as a high-end HSF, minus the incessant buzzing of a high cfm fan.
This kit is comprised of two main components; a heatsink/fan unit with a Peltier element housed in the base, and a large power pack that fills a PCI slot. The kit is available in two flavours -- Intel and AMD. The only difference between the two, other than the shape of the heatsink that the Peltier module is attached to, is that the AMD version has a copper base (to better handle the higher temperatures of the Athlon XP processors), and also has two settings -- high speed and silent, with the high speed setting being substantially faster than the Intel kit -- once again to handle the hotter AMD CPUs.
The reason for the large power pack is that Peltier modules like to suck down electricity quicker than a brickies labourer downing a six-pack after a hard day’s labouring. A separate power cable extends from the rear of the PCI power pack, straight into your mains power. And yet it appears even with this measure, the SubZero 4G is severely underpowered. A separate LED case fan is also included to help keep case temperatures respectable, as the Peltier module will pump a lot of extra heat into your case’s guts -- not good news for PCs that are balancing on the brink of crash city thanks to overclocked components.
The PCI unit doesn’t just handle the power needs of the demanding Peltier module. One of the biggest obstacles with Peltier cooling is condensation build up, as the Peltier module can get so cold that water will condense on and around it. Water, plus PC components, equals BAD. The SubZero 4G overcomes this PC killer of a problem by measuring the temperature of the CPU as well as the ambient case temperature, and adjusts the flow of current to the Peltier to make sure that its temperature never goes below the dew point (the temperature at which water condenses). It’s an effective solution that will no doubt be mimicked in future shrink-wrapped Peltier kits.
For a Peltier to be effective, it needs to consume a lot of power -- up to 150W to be precise. Yet the SubZero 4G only consumes a maximum of 73W, making this one severely underpowered unit. And it’s for this very reason that the SubZero 4G is only marginally more successful at cooling your CPU than a rubbery cheese slice.
Thermaltake claim that the Intel kit is suitable for CPUs at up to 4GHz, while the AMD kit is quite comfortable taming a 3400+ Athlon XP. Yeah, and purple winged monkeys are about to start shooting out of my butt. They also claim that this kit can be installed in 90 seconds -- thank God they didn’t mislead about one thing; installation is as quick and easy as advertised.
Performance on the other hand. . .
We used Chernobyl to test both the AMD and Intel versions. It was set to output 60W (roughly the same thermal output as a 2000+ Athlon XP) and then 80W (roughly the same as an overclocked high end CPU). For comparative purposes we used Intel’s Orb-like reference cooler that ships with the 3GHz P4, and a Thermalright SLK-800 with a Delta EFB0812HHE 4,550rpm 80mm fan strapped on top. Ambient temperature was a constant 21 degrees Celsius throughout the testing.
As you can see from our benchmark results, the SubZero 4G was thoroughly trounced by both heatsinks. And we’re talking Iraq going to war with America trounced. We remounted and tested each unit twice, to make sure our results were accurate. They were. Sure, the AMD SubZero 4G was much quieter than the SLK-800, measuring XXdB compared to the Delta fan’s XXdB, but with such woeful performance this kit is only good for those with a serious grudge against their CPU.
Adding further insult to injury is the cost of both kits. At a smidge over $250, you could easily put together a much higher performing Peltier kit of your own at half the cost, although you’d then have to deal with the woes of water vapour.
As a result we simply can’t recommend either of these kits. It must be remembered that this is Thermaltake’s first attempt at mass producing a Peltier kit, so we’re hopeful that the next version has much improved performance. Until then, don’t say we didn’t warn you.
Issue: 137 | June, 2012