Cooling Comes Full Circle
Our history with sub-ambient cooling goes back to the early days of this site, with our discussion of Kryotech’s first phase-change cooler in 1997 and our test of the improved version in 1999. Our 618 MHz Celeron quickly gave way to 800 MHz and 900 MHz Athlons, and even more cooling revisions pushed us past the GHz barrier less than a month later.
And then the competition showed up. Before Asetek became the purveyor of low-cost liquid cooling, its VapoChill phase-change system streamlined case and cooling components to a single box that supported processors from both AMD and Intel. By the time Prometeia threw its hat into the ring Kryotech had vanished and we had blown past 3 GHz. A few more improvements got us to 4.1 GHz, but reaching the next level would require a major improvement in either CPU technology or cooling capacity.
Liquid nitrogen cooling on the CPU and a phase-change cooler on the chipset finally allowed us to go beyond 5 GHz six years ago, an effort that inspired competitive overclockers the world over. Of course it wasn’t practical, because there were no practical 5 GHz solutions at that time. It wasn’t until Intel released CPUs on its 32 nm production process that “permanent” cooling solutions began to look viable for achieving these speeds. In fact, Chris Angelini was able to boot at 4.93 GHz using his Core i5-655K on air.
The technology was now in place to forgo temperamental liquid nitrogen cooling in our 5 GHz efforts, yet reaching this speed on a low-cost CPU that was already capable of running stably at 4.6 GHz with air cooling would have appeared trivial. The performance of a 5 GHz dual-core in a world of quad-cores would have been likewise laughable. We needed a properly high-profile, high-tech CPU to make this article worthwhile.
We knew we had a the perfect start for our project when Intel finally released its six-core, twelve-thread Core i7-980X Extreme Edition in March. A cooler with adequate capacity would still be required, and FrozenCPU.com matched us up with the hardware