Wowie, I hope that's not the Prescott model 2.8E - I had that and it got hot real fast. Could only overclock to 3.1 or 3.2, but keep it at 3.0 just to be safe.
What I got when it was new (July 2006)*:
Processors and Board
Core 2 Duo E6600 2.40GHz, 4MB Cache, 1066MHz FSB
XFX PV-T71G-UCF7...