Asus Overclocking Competition: Life Is Better With LN2

Asus hosted an overclocking competition this past weekend and invited us out to see XtremeSystems, OC Alliance, and Team PURE vie for top honors and performance world records on both LGA1366 and 1156. I've got experience working with single-stage phase changers, which use air-conditioner compressors to cool a CPU down to roughly -50C, but liquid nitrogen-fueled overclocking is an altogether different kettle of fish. It's also firmly in the "don't try this at home", although the price of LN2 most likely makes this a moot point.

The Rampage III board here is being prepped for subzero overclocking. The substance being applied is kneaded eraser. I've used mastic tape for the same purpose, but kneaded eraser is easier to apply, can be shaped to fit around socket components, and is less likely to contain small gaps that allow condensation to penetrate down to the motherboard. Mastic tape, quite frankly, is a pain in the butt to work with—imagine trying to seal the various nooks and crannies of a motherboard using thin, relatively narrow strips of tar that latch on to any surface they touch, fuse with previous stripes, resist cutting, and stretch. God help you if you actually plan to reverse the modification; mastic tape doesn't come off easy. The compound can be dissolved, but only if you're willing to invest in a lot of lighter fluid.

There are other ways to seal motherboards (neoprene and sealant solutions are also used), but the idea of a superior solution that uses inexpensive art supplies caught my eye. Low-temperature overclockers are generally the only people who go to the trouble of sealing a motherboard, but they aren't the only group that could benefit from the practice. While there's no need to seal a water-cooled motherboard (unless you've integrated a chiller unit), doing so could provide additional insurance against the possibility of a random leak destroying an awful lot of expensive equipment.

By the time the team was finished, the Rampage III was entirely covered with but the PCI Express slots and RAM visible.

Here we've got the full-sized LN2 canisters and a liquid nitrogen pot sitting on a motherboard. Overclockers pour the LN2 into the pot where it quickly evaporates, carrying away the excess heat of the CPU. The initial evaporation is visually impressive (seen below, but caught on a different system with a different pot). As we've noted, single-stage phase-changers can take a CPU to -50C or so without a problem; liquid nitrogen can lower the processor temperature down to ~-120C or lower depending on the scenario. If that's not enough, liquid helium, with its evaporation point of -269C, is sometimes used. AMD hosted a liquid helium event last year that yielded the still-standing record for fastest Phenom II overclock at 6.89GHz, but unlike liquid nitrogen, liquid helium can be dangerous. As it evaporates it builds up in the atmosphere of a room (usually right around head level), which tends to have negative effects on those of us who breathe oxygen. Adequate ventilation (or a team of overclocking midgets) are required if you want to play with fluids whose evaporation temperatures are easily expressed in terms of absolute zero.

It's impressive AND it's frozen. Two for one deal.

Asus' dual 5870 "Ares" video card...
Some of you had a hard time seeing the card outline in our article; we've included an outline that should help.

We've already discussed the Asus Ares, but the card is impressive enough to include an additional shot of it here. In a way, both the card and the overclocking event itself are examples of how rapidly computer technology continues to advance. In order to increase the GPU and memory clocks 15 and 20 percent, Asus had to bolt on a heavier cooler, beef up the card's power plugs, and bin a select number of parts that could tolerate the additional stress. In 2-3 years, we' will see midrange GPUs delivering equivalent performance with single-slot coolers and fairly quiet fans. (That's not to say we wouldn't like an Ares now.)

As for the main event, OC Alliance was leading the LGA1366 bracket as of Saturday evening, with a new world record (according to Asus) of 6.53 GHz. At 6.5 GHz these systems are running at nearly twice the speed of Intel's current highest-end Core i7s. We don't expect to see Intel cranking up its clocks in the next 24 months—those days are over—but Francois Piednoel, one of the Intel reps who attended the event, emphasized to us that improving single-threaded performance is still a focus at Intel. Francois acknowledged that it's much harder to extract additional IPC efficiency now than it was in years past, but the company is still committed to the goal. We don't expect to see any jumps that mirror the move from Core 2 Duo to Core i7 anytime soon, since pulling the memory controller on-die is a one-time benefit, but Intel is scarcely out of ideas.