[Psycho101]

If you can get an E0, you'll likely have (not always though) a lower VID or at least be able to get the same clock speed as a C1 with less, sometimes much less voltage. As per the E8xxx series, E0's are 9 times out of ten significantly better over clockers than the older stepping.

If you go for a Q9650 then you're guaranteed an E0 stepping, where as with the Q9550 you could get the C1 if the seller doesn't shift much inventory. Not the end of the world, but still a disapointment IMO. You'll likely top out at 3.8Ghz with a C1 on reasonable volts, and stop at around 4GHz with a high Vcore. E0's can potentially go 4.1GHz+ with in spec voltages and LLC, depending on your luck.

The Intel cooler is good for stock speed, and is relatively quiet. However it handles overclocks poorly. I believe the Quad core stock HSF has a copper bottom plate, like a cylinder of copper with the aluminium fins soldered to it. The cooler that came with my E7400 was just aluminium, and was painfully thin. It definitely wasn't up to the job of cooling my Q8200, with idle temps at 51c and loads of 78c. If the standard cooler you get with the quad isn't copper cored or is around 3/4 of an nch thick, it's the same as the dual core version, and I wouldn't use it.