Ram upgrade

what is the difference between the DDR PC2100 and the DDR PC2700? there only a little price difference.

DDR PC2700 is faster.

What are you going to put the RAM in?

i was just lookin for ram for my new ibook.

From Apple:
IMPORTANT: Use PC2100 DDR266 SO-DIMM for 133Mhz system bus iBook. You should purchase DDR-SDRAM SO-DIMMs that have been tested and approved for your system. If you don't purchase memory directly from Apple, be sure to check with the third-party manufacturer to verify compatibility before purchase.

From what I've found with researching memory for my Mac is that you just have to buy high quality RAM. They use the same memory as PCs, but their systems set the memory to a default settings, where as PCs can adjust their memory settings to accept a wide variety of RAM. If you were to purchase PC2700 memory, it would just downclock itself to run at PC2100 speeds. If there is no price difference, I would buy the PC2700.