So I just pulled my 1GHz TiBook out of the closet for the first time in a while, only to find that it's now forgetting the date & time and leaving the L3 cache disabled on every boot. Sounds like a dead PRAM battery to me, so I'd like to replace it. Problem is, as far as I can tell, replacement TiBook batteries start at $30 and go up from there, as compared to $3-8 for CMOS batteries on PC laptops - yargh! What I'm wondering is if there's any reason I can't use a cheaper CMOS battery with a similar connector. From the replacement guide on iFixit, it looks like it has a three-pin plug with all three pins wired to the PCB they've placed the battery on - there isn't some kind of proprietary battery-ID mechanism, is there?