I have a 3800+ X2 and unfortunately I got a CCBWE 0541 which is the worst stepping for OCing yet. With my XP-90 I can only get 2.5 ghz @ 1.52 VCore but I run it @ 2.4 @ 1.45 VCore to keep the temps down. Anyway it is MUCH smooter in pretty much everything, most noticably multi-tasking and alt-tabbing out of games (which pretty much multitasking, heh) Anyway I don't regret my decision to go dual core, it just sucks that I got a bad stepping but to tell you the truth you probably aren't going to notice any difference between 2.4 and 2.6 or 2.7 or whatever in anything other than benchmarks and possibly HL2. HL2 is the only thing other than benchmarks that I saw jump up noticably from OCing, but to me it was worth, and why wouldn't I OC? Anyway I would say go dual core, get an Opteron 165 if you can find one for a good price (although recently it seems that the OC's on Opty 165's are getting to be about the same or actually worse than the X2's) or get a 3800+, and just pray when you open the box you don't get an 0541. Even if you do, you will still be able to get at least 2.4Ghz and that's a $630 processor for $320... Not bad...