I had more RAM put into my MacBook Pro today (from 4GB to 8GB). They gave me back the old RAM cards, which say 2GB 1Rd8 PC3-10600S-09-11-B2. Assuming that my old PowerBook G4 does not have 4GB RAM, which I’m pretty sure it doesn’t (Maybe it has half a gig?), can I use these cards in it?
You need to give more specific information about which generation they are or the manufacture date. As far as I can tell only the last generation of G4 used DDR2, while Pros are mostly DDR2 and DDR3. You won’t be able to use the wrong type of RAM, and if you look at the pins on the bottom there should be a different number of them and probably won’t fit otherwise.
I can absolutely guarantee that a G4 Powerbook and a MacBook Pro use different types of memory.
Make earrings out of them.
They sure aren’t worth anything (the enormous cost of the new cards notwithstanding).
What? If you’re saying you now have 2x 4GB DDR3 sticks, that should have been about thirty bucks.
Well, it’s an Apple dealer so they got me for $98 plus installation. It’s not like I had a choice. 
Does changing the RAM in a Mac yourself void the warranty? Just wondering, as I’ve always done RAM and harddrive swaps myself on MacBook Pros (not that it matters, I guess, as I don’t get the extended Apple Care and by the time I get to this, I’m out of the warranty period. Just wondering if that’s why you’re saying you didn’t have a choice.)
I have come to the conclusion that there are certain things I should not try to do myself. While I have done stuff in PC towers with success, opening up a laptop would be like someone attempting to fly an airplane after having only played MS Flight Simulator: It can be done, but the chances of a suboptimal outcome are high.
The answer is no, it doesn’t void your warranty.
Good to know in case I’m working on someone’s computer or advise them to do so. (I do know about the Macs with the RAM soldered to the logic board that are not upgradeable.)
Posting from a MacBook Air, that I myself have replaced the flash hard drive, and the battery. Actually a really easy swap. Have changed the RAM and hard drive on a MacBook Pro as well.
Next time, take the risk and do it yourself. Unless you try to do it with your toes, it will be easy.
Those old DIMMs are as useless as the PowerBook G4 you want to put them in.
The PowerBook G4 is not useless. Neither is my 2001 iMac (although it’s in storage). They both connect to the Internet wirelessly. I can log into work on either of them and get my job done, and for that purpose they are just as fast as the machine I’m on now. As for browsing, SDMB doesn’t take that long to load. I don’t stream music or videos, and I don’t play games. So the PowerBook G4 is a useful backup machine. And before I got the MBP, the iMac saved my bacon a few times. It’s good to have a Plan B.
Moderator Note
That’s not a helpful comment. Don’t threadshit.
And to be sure, the latest G4 requires DDR (first edition.)
But the ram you have is PC3 aka DDR 3.
" PC3-10600S " = " DDR3-1333 1333Mhz 240pin So-dimm memory Ram upgrade"