Can I use DDR2 memory in a 3-4 year old laptop that originally had DDR ram in it?

(I posted DDR2 SODIMM pc4200 Ram on Craigslist, Kijiji 3 hrs ago, and had 2 callers ask...)

Thanks,
P

The sockets and timings are typically much different for DDR and DDR2. I wouldn't attempt to use DDR2 unless the PC (or laptop) calls for it.

Answer is absolutely not. You cannot use DDR2 interchangably with DDR