The curious case of the P8P67 Pro and resuming from sleep

I recently upgraded my development PC to an i7-2600k based setup, based on an Asus P8P67 Pro motherboard. Throw in a new OCZ Vertex 3 SSD, overclock to 4.3GHz and it's blazingly fast.

However, whenever the system awoke from sleep, there would be no video output - frustrating to say the least. The only way to resume was a hard reset of the entire system.

I eventually tracked this problem down to an obscure setting in the BIOS related to the overclocking - 'Internal PLL Overvoltage'. Not exactly something you would imagine would be related to ACPI or sleep settings.

Disabled this setting fixed the problem for me - thanks to the overclockers forum for the tip-off.