We managed to score some interesting information on upcoming Nehalem based, quad-core Clarksfield CPU and we can now confirm that the fastest one, branded as Extreme Edition, will work at 2.0GHz. Don't be disappointed with the speed, as with a little help from the Turbo feature, it will be able to overclock at least one core to 3.2GHz .

The CPU has four cores and support for eight hyperthreaded ones, DDR3 1333 as well as massive 8MB of L3 cache. It will use socket rPGA Socket G1 and it's 37.5mmx37.5mm in size. This fastest Intel quad-core notebook CPU, that is set to be the performance king of the Calpella platform will have an extremely high 55W TDP (Thermal Design Power) and it won't do particularly well with the battery life. 

Notebooks based on this CPU are expected in Q3 2009, most likely they should launch in time for the back to school period, or late August, early September time.