Two Interesting Overclocking Results
We have a little surprise for the overclocking lovers reading this report. In addition to the Core i7, our contestants were able to try out a Phenom II, from the next generation of 45 nm Phenoms expected in January.
4.95 GHz for the Phenom
Though AMD claims they’ve reached close to 6 GHz, we were able—with the help of JMax—to reach “only” 4.957 GHz. We should point out, though, that the factory speed of the processor in question, a Phenom II X4 940 BE, is only 3 GHz. We used the processor on a Gigabyte AMD 790GX motherboard, with DDR2 RAM (as required by the AM2+), and a liquid-nitrogen cooling system. This processor may have the potential for higher clock rates, but it had the unfortunate tendency to freeze as soon as the temperature dropped below -70°C.
To see what the processor was able to do, we ran a few tests at a stable frequency (4 GHz). The processor was able to perform a SuperPi 1M in 17.769 sec. During other tests using samples, the processor was able to boot up even when chilled to close to -200°C!
(Ed.: In preparation for benchmarking Phenom II, I asked AMD about the overclocking results garnered for our Phenom II sample under the influence of LN2. The answer was that the HyperTransport link was limiting scalability. If you're going to take the chip to extreme frequencies, you'll want to drop down to 1 GHz or so on the HT interconnect rather than its default HT3 speeds. On air, however, HyperTransport shouldn't be a limiting factor.)
5.28 GHz For Core i7
With a limited amount of time left—the contest was over and the other competitors were packing their gear—and with a limited quantity of nitrogen, we asked the French team to overclock the Core i7 for maximum frequency. They managed to log 5.287 GHz with the Core i7 965 test sample, and even went as high at 5.3 GHz (though not stably). The cooling system used liquid nitrogen and the motherboard was an MSI Eclipse, obviously using the X58 I/O hub. The memory was DDR3 supplied by Kingston, and no problems were encountered with it. In fact, with a frequency of 5.287 MHz, our processor placed in the Top 10 worldwide, copping ninth place (according to Ripping.org). It’s a result our overclockers can be proud of.
