case solved!! it was the case... changing the case fixed the problem!!
Hi, i plugged it directly to the imac... i think the case can not power up the drive... Tomorrow a friend of . mine will drop off his case to try with that ...
Great guide!! I just upgraded my mid-2010 27" imac to 20gb of RAM and an SSD. I then tried to plug the old 1tb HD (Seagate) to an external usb case for 3.5" HDs, but the drive does not spin up at all.... The case is definitely functional since it operates now with another HD connected to it...I have not tried a second case, since i do not have any... any ideas why the HD is failing?