I recently sold my PB with 1.67GHz, it was the last model series to use DDR1 memory. I sold it with quite bad battery, in terms of capacity that was. I also had one unused which I had owned for some time already so I finally got the change to test it, it worked fine, I ran the machine on battery power, then charged etc. It had only 3 battery load cycles so it was almost like new. I sold the battery separately. Today the owner received and said that when he plugs in the battery his PB powers up straight away and does not react to power button, especially this last thing surprises me. When he removes the battery the machine works OK. SMC reset has already been mentioned, dunno if it worked. But, is the battery damaged? He checked the battery model number and says it is compatible.