When it comes to cooling hot processors, you can't beat a phase change setup. Sure Liquid Nitrogen offers users lower operating temperatures, but it's not a viable 24/7 solution. The Prometeia Mach I can run indefinitely.

Originally, the Prometeia Mach I used R134A coolant but since I was never able to leave well enough alone, I had it recharged with R404A. That means my test bench Mach I will be able to reach a lower operating temperature and have a higher cooling capacity than a stock Prometeia Mach I/II cooler.

With the Mach I installed on the Athlon64 3500+, I started at the beginning again because I thought it'd be interesting to see when and where I'd have to raise the voltages.

Things were very uneventful until I hit 240 MHz (2.64 GHz). Raising the voltage slightly to 1.6V stabilized the system at this point.

Further on, I had to raise the chipset voltage to 1.65V at 253 MHz otherwise the system would BSOD randomly during the benchmarks. At 264 MHz (2.90 GHz) the memory started to top out, and I had to lower the memory divider from 1:1 to 9:10 (the timings of 2-2-2-5 were kept). Increasing the memory voltage past 3.4V didn't't help in this case.

To get past the 270 MHz (2.97 GHz) mark, I had to increase the processor voltage all the way up to 1.85V as well as decrease HyperTransport to the 4x multiplier. Without these changes, the system would not boot. The little Athlon64 3500+ maxed out at 277 MHz or 3.05 GHz; no amount of voltage tinkering would allow us to stabilize the system past this point.

Believe it or not, the results I got from the Newcastle core Athlon64 3500+ are below average for this type of cooling. Too bad I got a "dud". It still feels plenty fast though!

PCStats Test System Specs:

processor: amd athlon64 3500+ clock speed: 11 x 200 mhz = 2.2 ghz motherboards: dfi lanparty nf4 sli-dr (nf4-sli) videocard: msi rx800xt-vtd memory: 2x 512mb corsair twinx1024-3200xl hard drive: 40gb wd special ed cdrom: sony 16x dvd-rom powersupply: pc power & cooling turbocool 510w software setup windowsxp build 2600 nvidia nforce4 6.39 catalyst 5.3 benchmarks SiSoft Sandra 2005 Super Pi 1.1 Hexus piFast 4.1 ScienceMark 2.0 Beta PCMark04 3DMark2001 3DMark05 Comanche 4 UT2003 UT2004 Doom 3

We did not run any office benchmarks because no one would overclock for faster word processing... really, trust me, they wouldn't.