Overclocking
Core-for-core, overclocking allows nearly any modern CPU to top the performance of its most-expensive rivals.
Our original PC was able to reach an incredible 4.35 GHz using the same-specification Core i7-950 CPU, motherboard and heat sink, so we had high hopes for this one. We even copied the overclocking profile from the original build to today’s alternative build in hopes of using it as a starting point. Unfortunately, this CPU was not as cooperative, forcing us to choose between a lower multiplier or lower base clock to reach its lower maximum stable frequency.
Higher-quality RAM in today’s build allowed us to use a 10x DRAM multiplier to achieve DDR3-1760.
We kept the CPU core at the 1.40 V setting in hopes of promoting longevity. Our experience shows that on Intel’s 45 nm process core, 1.45 V causes deterioration in the first few months, while 1.40 V forestalls that damage for over a year. Your results may vary.
Rated at 7-8-7-20 timings at DDR3-1600 transfer rates, Kingston’s HyperX modules required slight latency increases to cope with the higher frequency. Response time increases only slightly, since our math shows that DDR3-1760 CAS 8 has the same response time as DDR3-1566 CAS 7.
CPU-Z shows the resulting frequencies of our successful—though somewhat disappointing—overclock. Stability tests prove its validity. Some readers will blame our slower CPU fan for the less-dramatic top O/C, but Real Temp showed that heat was not a problem for the CPU. Remember that we were forced to slow down the super-fast fan in our original build to retain our sanity through benchmark testing. Luck-of-the-draw gets credit and blame for the original build’s super-high stable frequency, as well as today’s more modest limitations.
Troubles reaching a stable overclock with our graphics card were quickly resolved once we remembered that AMD Overdrive affects only one GPU at a time. Setting both to the same setting allowed us to push the limits at roughly 10% over stock.
