...and then a manufacturer (possibly Compaq or someone more esoteric like Mannesmann Tally), came out with a Mini-tower design and a few arrived at work. Seeing how 'cool' this new arrangement was, some of our engineers took their IBM PC units off their desks and sat them upright at the side.
A few weeks later, the IBM PCs started to die because the retrofitted 5.25" full height hard disks (probably 10-20MB!) began to seize up - the spindle bearings had 'worn in' in one orientation and didn't take too kindly to being tipped on end. Sometimes a good whack would get things moving - if not, it was time for a new (and very expensive) hard disk.
http://upload.wikimedia.org/wikipedia/commons/f/f1/Ibm_pc_51...