I just wanted to tell you that I replaced my BP6 (with another one, of course ) after I noticed that many caps were bulging. It still worked flawlessly, the only indicator that something was wrong were obviously very high chipset temperatures. I first thought MBM5 had gone crazy (90°C? ) but now I´m quite sure the chipset really got hot because of the dying caps (maybe not THAT hot).
All of them, IIRC. Definitely some caps around the CPUs, plus the ones in the middle between the "left" CPU (close to the outside connectors) and the expansion slots.