Well 4.5Ghz was ridiculously easy to obtain. I was able to do it with only 1.30vcore too. Temps full load after Prime blends 2hours + top around 66C. With my GTX460 at 900Mhz core I pull a P4560 in 3Dmark11.
Ill probably toss in a 560Ti next month... but for now this system seems rock solid