well as far as broken goes, look for burn marks and damage. It's hard to visually find defects, so you have to test it out in a compatible motherboard.
EDO ram is pretty stubby with very large black things
PC 100 and 133 are divided into 3 sections of pins, whereas all DDR ram is divided in 2 sections of pins, bearing 184 pins.
Just do a little research as to this, run a search and google it. see what you come up with.