Not that I don't believe anyone who has ever pointed this out, but I just downloaded Crucial's "Mac System Scanner" and these are the results:
Your Apple PowerBook G4 1.67GHz (15-inch Display) DDR2 Specifications
Currently installed memory:
1GB DDR2 SDRAM
1GB DDR2 SDRAM
Each memory slot can hold DDR2 PC2-5300,DDR2 PC2-4200 with a maximum of 1GB per slot.*
*Not to exceed manufacturer supported memory.
Maximum Memory Capacity: 2048MB
Currently Installed Memory: 2GB
Available Memory Slots: 0
Number of Banks: 2
Dual Channel Support: No
CPU Manufacturer:
CPU Family: PowerPC G4 (1.5) 1.67 GHz
CPU Speed: 1670 MHz
All memory slots may be filled, some of the existing memory may need to be removed in order to upgrade.
Q: What memory goes into my computer, and can I mix speeds?
A: DDRII memory with support for DDR2 PC2-5300, DDR2 PC2-4200 speeds.
Because DDR2 memory is backward-compatible, you can safely upgrade your system with any of the guaranteed-compatible DDR2 speeds listed below.
I wish I had this confirmation because OtherWorld Computing had a clearance sale on PC5300 modules pulled from Apple machines. They were $15 each for a 1GB module. They had 340+ units available and in a few days, went to zero. I unfortunately didn't save my basket/cart.
Here's the link to their, Crucial's, "System Scanner":
[http://www.crucial.com/systemscanner/MacOS.aspx]
