I upgraded my hard drive to 1tb in my iMac 20" aluminium desktop. Everything went well, tested before I put it back together and all was well. Then I done the most stupidest thing putting it back together. The LCD temperature sensor cable must of dropped down when I put the metal brazil back on, then I screwed right through it, splitting the cable. Now, the fan starts up really loudly and I am getting no picture. I know I need a new cable but I have searched everywhere but I cannot find one. I don't really want to get it professionally repaired, as it will cost a fortune for what only is a single cable. Any advice on where I go from here will be much appreciated.