Hardwarecanucks posted a review of the Mushkin HP-580 580W Power Supply

With its newly reduced price and great looking specifications, the Mushkin HP-580 is definitely high on many consumers wish lists. Unfortunately, after reviewing both the Mushkin HP-550 and the XP-650 power supplies, we had high expectations which this power supply simply failed to meet. While most of the performance numbers for the HP-580 are acceptable for a budget unit, the voltage regulation on the +12V rails left much to be desired.

Mushkin HP-580 580W Power Supply Review