Har drive?

[desi1983]

guys i bought a segate 120 hard dirve. it should work with the mac book, but when i replaced the hard drivem the mac did not find the harddrive. so then i used it as a hard drive, but even then it didnot find it, but i went to disk utilities and verified it....n then the macbook 13.3in ofund it and i wa sable to read n wrte to it. so now i decided to tyr replaceing the stock 60gb hardrive one more time...but it still did not work, when i put the hard drive in the mac, the mac wont fidnt the hardrive. so right now im using it as a external, so i wanted to know am i supposed to do something else?...or is it that that hardrive wont work in the macbook....so...if any one can help..i would really ppriciate it