I just recieved this batch 3717A922 from newegg. I can't find any information at all, I can't even find another stepping with a number as the first digit. I am using a 650i MB with this chip and so far its at 3GHz, but I havent loaded windows yet so I can't tell anything yet. Anyway this is the rig.

6420 3717A922
MSI P6N-SLI
Balistics 6400
BFG 8600GT
Seasonic S12-600

I will post more when I get some testing done.