"Overclocking the Sapphire Pure Black X58 initially was met with a lot of failed boot attempts until I figured that the voltages needed were a bit different from the values I've needed in the past. Not so much different but one in particular that I had never really needed to adjust before was the IOH/ICH I/O voltage. This voltage helped bring stability to my overclock at 210 x 20. The board could boot up to a bclock of 218Mhz and make it into windows at 214Mhz but good long-term stability was only reached at a bclock of 210. This of course done using air cooling. I used a combination of CPU vcore, CPU vtt, IOH/ICH I/O voltage and DRAM voltage to increase the speed of the processor ultimately giving me a 4.2GHz stable OC."
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