20GB to 160GBs
4,200 RPM; 5,400RPM or 7,200RPM
Cache varies 2MB,8MB and 16MBs
Warranties vary ...believe Seagate has 5yr, Hitachi 3,

NEWEGG is a good source, they have a nice way to look at drives by price, capacity, mfg., etc, and they have buyer reviews that are usually worth looking at.