I am encountering some problems with my new Pi Rev B. It was working fine, but it started having issues where it would only illuminate the red LED. I tried a few known good SD and even re-imaged one. I tried using my serial cable, USB and bench top power supply to eliminate it as a possible problem. Voltage across the test ports was 4.2 or low. Any attempts to power the unit will make the voltage regulator hot to the touch. At this point, I am hoping for a poly resistor reset.
I was using a wi-fi adapter, keyboard and mouse and HDMI. Tests were done without anything attached. Any thoughts on what to try next? It won't even turn in at this point.

