In light of the price cuts on S939 X2's, I'm considering upgrading my S939 3700 SD to an X2 of some kind. The 3700 is mildly clocked to 2.5GHz, making it around a 4100-ish in performance terms. I play FPS shooters, Doom 3 and Q4 etc, but also do a fair bit on DVD encoding and burning, as well as general Windows work. Which S939 X2 (if any) would be a worthwhile upgrade, or should I wait until next summer and do the old CPU-Mobo-RAM upgrade to whatever dual core CPU is best at the time?