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Overclocking quad cores
When the QX6700 arrived, I didn't think it be a very good overclocker because the more cores you add the more likely you are to get a duff one included.
In the olden days Intel or AMD would make a load of processors and test them afterwards. Cores with good characteristics were set to a higher frequency and cores that didn't quite cut the mustard ended up as lower clocked processors. When you have four cores that all run at the same frequency, this selection is a lot tighter and maximum speeds are limited by the best core out of four.
At first overclocking was a nightmare with the D975XDX2 'Bad Axe 2' motherboard. Although we hit 3GHz with it, scores actually got a tad worse. It was only after we found a Bios update that we really got somewhere. The new Bios actually limited some of the FSB settings but we started to see bigger scores with higher clocks.
When we got too ambitious the system became unstable and the Bad Axe 2 was really difficult to reset back to stock clocks. The competition does Bios resetting and fine-tuning settings much better but that doesn't matter to Intel since they focus on the business market in the likes of Dell and HP.
We found that without increasing the voltage to the CPU (thus inflicting minor blows to it) we could push the frequency to 3.2GHz reliably. It booted at 3.33GHz once but we forgot to run benchmarks… (the benchmarks probably wouldn't have run stably anyway, ahem). At 3.2GHz the quad core was 90 per cent quicker than an X6800 in 3DMark05 CPU tests.
In the coming weeks we believe we can push the processor to 3.66GHz, representing a 1GHz overclock, with just a few minor voltage tweaks so keep your eyes peeled.



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