That depends.. my RIIE is a POS, I have a board wall at 212 (213 3D starts getting funky), 214 and up no boot. I tried 5 CPUs already, 3 of which are Gulftowns that ran >230 on other RIIE's, just not this one :(
That's why I bought Karmakazi's E760, just waiting for Shamino to release the new bios with Q3QR support ;)