PS3 Blu Ray drive change over

Hi lovely PS3 peoples!

Im in a bit of a pickle, i have an old style 40gb PS3 that used a 400a optic drive, unfortunatlyit died, depressing i know, but then i bought a new 400a optic drive, took the old chip board thats attached to the drive and whacked that on the new one as well, as i read that this chipboard and the motherboard are linked, problem is nothin is being read with this new drive, everything does as it should makes all the noises, blue light comes up but no recognition of a game comes up on the XMB, so any ideas from out techies on here??

PS Sorry this is a very lame first post im just kinda desperate to get back online for some COD