Buzzing noise after reassemble

[puelocesar]

Hi everybody, I changed my iMac's hard drive to a SSD, following the iFix It guide. It all worked well, but after some hours using the machine, a buzzing noise appeared in the top left corner of it.

I read in the forums people having problems with defective PSU, but mine was working fine before disassembling the iMac. What do you think I could've made wrong in the assembling?

Thanks

 

[mdhwoods]

Really no way to determine without opening it up and powering it on to see where the noise is coming from. I could be as simple as something loose or as serious as something going bad. Without opening it up to determine where the noise is coming from would be just a bunch of guesses.