
Neither the XP2000+ nor XP2100+ o/c much if at all, just like the XP2200+ and they all run very hot. They are well priced though and stock perf is very good. If you do want to o/c then XP1800+ or XP1900+ are my recs as they tend to hit XP2100+ to XP2200+ speeds without the need for your mobo to cope with insane FSB speeds as is the case for XP1600+. The added benefit is the small added cost over XP1600+ and the guarantee that even if stuck at stock speeds you'll still get great perf!

If you are feeling either patient or rich the XP2400+ (or higher) using the new 0.13mu T.bred-B core are a fair bit faster than they sound due to AMD revising the way in which the XP rating works (unofficially to account for the boost P4's get from 512k cache and 533FSB) so XP2400+ is faster than it actually sounds compared to XP2200+. These CPUs should o/c very well and run much cooler, the XP2800+ uses 333FSB which really get the speed and benefit from DDR333-PC2700. All these new CPUs are still rare and expensive, so it may be best to wait, possibly buying an XP1800+ to XP2100+ to tide you over.