Depends, what apps do you run? Core-per-core, Phenom II can be competitive with anything Core 2 offers, and you'll be getting twice the cores. You won't even have to work THAT hard to get a 955BE running at 3.6 ghz if you want to overclock it (might even go higher; 4 ghz is not unheard-of, especially on C3 chips). The 955BE would, at the very least, be just as fast; in multi-threaded apps, it could be much faster. Just be sure to get a C3 chip if you do go for the 955BE!