Recently we are seeing many iMacs with broken hard drives. One reason could be a that when you move the screen you are also moving the hard drive. The hard drive has got plates that spin at a very high speed and if you move the computer while the hard drive is working you may break it.
Today we fixed a 24 inch Intel iMac for Honna Planning Office. It is a design company so a good performance of the computer and data integrity are very important.?The hard disk was failing after a few ours but the data could still be read so we replaced the hard drive and recovered the data from the old hard drive.