I did have it at 4.2 for a while, but the temps started to concern me. At moment (at 4.08Ghz) under 100% load, temps get to about 63, 60 with an appox 26-27 degree ambient. If I had a water cooled set-up, it would be a different story, still have heaps of room to move with my vcore
So this is a PI run for my Road Cone, haha. I overclocked it to 2.14ghz from 2.0...that's about all this thing can handle, lol. I'll try it again when I have better memory in it.
By the way, it's actually a XP 2400+, but it reads as a 2600+ when it's overclocked.