I've got the 1.33GHZ 17" PB running Panther. I've tried 2 Kingston 512MB ram sticks in it so far. Each one resulted in lockups and freezes galore. No problems at all with the original 512MB OEM stick. Will these Powerbooks only accept Apple ram? I've read here about the stringent 10.3 requirements, but has anyone else got 3rd party ram to work? How about Kingston? This isn't the cheap ValueRam stuff. Any other suggestions?