Hi folks... First all of im new to the forum.. so let me just hello, and merry chrimbo to you all... Right, i have a 24" Imac 8.1 C2D 3.06ghz.. Currently have a 500gb hd (all i can tell you about the hd as it wont boot up) A few days ago i was using my computer fine then all of a sudden it froze and then the screen started flashing at me.. I had to turn it off as it wouldnt do anything else.... For a day thats all it would do.. I would start it up all was fine then it would staqrt flashing and crash... I spoke to apple on the phone and they said it sounded like corrupt software.. They took me through the reset thing, shift p + r was it? that wouldnt work, so they said to put in my snow leopard disc and boot up using c to run from disk utility and repair drive etc... However it wont even do that.. it just comes up with the normal white screen with the apple logo then just stays there and will not go any further... Ive accepted that a new hd is needed, fair enough, to be fair it was slowing down quite a bit before all this, and was starting to play up... What HD is recommended to replace what i would have in there now. Ive been looking at WD Caviar Black.. I need something this is reliable, resonably quiet as i use my computer for audio editing production, also speed is very important as well... As im a bit of a technophobe would upgrading the size of the hd cause my computer to run hotter, burn out etc etc due to different wattage or something like that? Sorry if i sound like a complete moron, but i just want a nice simple exchange in HD with zero problems or issues.... If anyone can supply me with any help and advice i would very grateful.. Thanks in advance..