We used our overclocking-champion GA-EP35-DS4 motherboard to test the E8500 at its stock 3.16GHz, the 2.66GHz speed of its lower-cost E8200 sibling, and its best-stable overclock. Making for a perfect comparison is our overclocking-champion Core 2 Duo E6750 at its stock 2.66GHz speed plus its highest-stable overclock.
The GA-EP35-DS4 is Gigabyte's high-value, updated version of its P35-DQ6. Based on the same PCB as the EP35-DQ6, the only difference is its 6-phase voltage regulator, which is still more than adequate for overclocking Intel dual cores to their limit.
Achieving ultra-high bus speeds on a DDR2-equpiped motherboard could have been difficult, but our Crucial Ballistix DDR2-800 has proven itself capable at data rates up to 1252MHz using CAS 5 timings at 2.40 volts.
We already knew our Core 2 Duo E6750 could reach 4.16GHz at a 520MHz FSB clock and 1.50 volts. Using the same voltage, the Core 2 Duo E8500 climbed to 4.59GHz using a 483MHz FSB.
Of course, 1.50 volts really is too much for the E8500, given its smaller die size. Rather than risk the core on long-term testing, we backed the core down to 1.45 volts. At this level, many builders will find that the most effective CPU air coolers are perfectly capable of keeping temperatures under control. Here are the results.
A final "best" overclock speed of 4.46GHz at the 470 MHz FSB and a 1.45V core voltage put the Core 2 Duo E8500 a full 300MHz faster than the highest speed our Core 2 Duo E6750 could hit using similarly-stressful voltage settings.