[one swell foop]

Hi!

I'm trying to help my roommate upgrade her Power-book before I move to the other side of the country so she can have a more functional machine. I used Crucial.com's model compatibility search to find this: 1GB, 200-pin SODIMM, DDR PC2700 upgrades for Apple PowerBook G4 867MHz (12-inch Display) Laptop/Notebook, CT617391 from Crucial.com which is sort of ridiculously expensive for a gig of RAM at today's market prices(especially seeing as how I just upgraded a used PC laptop I bought off a friend to 2 Gigs for the same $90 it would cost me if I followed Crucial's advice).
Searching on Newegg.com for Mac RAM yield the following likely looking result:
Newegg.com - CORSAIR 1GB DDR2 667 (PC2 5300) Memory for Apple Notebook Model VSA1GSDS667D2 - Retail
For substantially less I can get something that is DDR PC2 5200 rather than DDR PC 2700 and as good or better than the crucial product. To be honest, I'm used to building my own PC's. I don't know what factors might make RAM at a higher spec incompatible, or not be able to be backwards compatible with old Mac hardware. Can anyone provide me with advice on whether or not the above product at Newegg.com might be compatible with this machine? If not, would anyone be so helpful as to provide a link to a specific 1 Gig stick of RAM that would be compatible with this machine, or at the very least give me a few laws of nature in regards to upgrading RAM in the Mac universe?
Thanks in advance for any advice and help!

[one swell foop]

Help please?

[mduell]

No, you can't put DDR2 in a DDR machine.
Yes, DDR really is more expensive than DDR2, for a variety of reasons.

Newegg has 1GB Crucial PC2700 for $81 and some other brands for as little as $60 (but they may or may not work in a PowerBook).