MadHacker,
I already did a check on the aluminum heat sinks and found +4.65 volts on one ... that one had a single IC that didn't have an insulation pad. I simply pulled one and a plastic screw washer from the power supply that died. (Waste not, want not...
)
On the other heat sink there was an IC without a pad too... but it was completely incased in plastic (i.e. - no metal heat sink tab) so it's insulated already.
I will check the copper "fingers" again before they are attached to the water block.