VR-Zone has put up a guide on how to voltage mod the P4 Northwood to set the default voltage from 1.5V to 1.85V.

By doing this mod, the board need not support any voltage tweaking and you will still be able to carry on with the overclocking. Also we have addressed the issue of the cold booting problem of the Gigabyte 8IRXP that occurs when there is manual tweaking to VCore voltage from the BIOS and this method will solve the problem.

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