It wasn’t long ago I was nostalgic about an old computer I saw back in the 1980s from HP. It was sort of an early attempt at a PC, although price-wise it was only in reach for professionals. HP wasn’t the only one to try such a thing, and one of the more famous attempts was the company that arguably did get the PC world rolling: IBM. Sure, there were other companies that made PCs before the IBM PC, but that was the computer that cemented the idea of a computer on an office desk or at your home more than any computer before it. Even now, our giant supercomputer desktop machines boot as though they were a vintage 1981 PC for a few minutes on each startup. But the PC wasn’t the first personal machine from IBM and, in fact, the IBM 5100 was not only personal, but it was also portable. Well, portable by 1970s standards that also had very heavy video cameras and luggable computers like the Osborne 1.
The IBM 5100 had a brief three-year life from 1975 to 1978. A blistering 1.9 MHz 16-bit CPU drove a 5-inch CRT monitor and you could have between 16K and 64K of RAM along with a fair amount of ROM. In fact, the ROMs were the key feature and a giant switch on the front let you pick between an APL ROM and a BASIC ROM (assuming you had bought both).
