IBM Personal Computer Model 5150

In 1981 PCW wrote a world exclusive review of the very first IBM PC. This is an abridged version to commemorate the 25th anniversary of the Model 5150's launch, which took place at a press conference in New York on August 12 1981.

With more than a little help from its friends, IBM has come up with a real stunner and, much to PCW's delight, has named it the IBM Personal Computer Model 5150.

Take a closer look at the 5150 and its various components

The system has much to commend it, both for serious and fun applications, since it can grow from a fairly expensive cassette-based configuration to a full-blown twin disk/colour graphics machine that offers the competition a fair run for its money. It almost goes without saying that the computer is well made, keeping up IBM's almost legendary reputation for quality.

After watching the growing personal computer industry very carefully, IBM finally cranked its own PC project into action about 14 months ago. The public was becoming aware of the usefulness of these machines and prices were dropping. This was enough for the grey giant and it made its move.

By swearing certain key people and companies to secrecy, IBM was able to discuss its plans with those who already knew what the microcomputer game was all about.

Microsoft, for example, was involved right from the beginning. However, at the moment the machine is only sold in the US. IBM will not say when, if ever, it will come to Britain.

The minimum configuration is in two parts: a system unit, which houses the memory, processor, loudspeaker, power supply and slots for up to five expansion cards; and a keyboard, connected by a six-foot coiled flex.

One or two 5.25in disk drives can be installed in the front of the system unit. A monitor or domestic television is also needed and, for those without disks, a domestic tape recorder with a DIN connection. IBM supplies an Epson printer as its standard listing device, although you can attach a printer of your own choosing.

The whole design is very pleasing and all the parts clearly belong together. Everything is designed with a first-time user in mind. IBM has gone overboard to make the system as easy as possible to configure and use.

IBM supplies a monochrome monitor with a very steady, clear display of 25 rows of 80 characters; a colour monitor or the TV gives you an option of 24 rows of either 40 or 80 characters. The graphics resolution is not as good in colour: each character is 7x7 dots in an 8x8 box, compared with 7x9 in a 9x14 box in monochrome.

IBM warns that certain televisions and monitors (not its own) can cause data errors on disk transfers unless the screen is at least 12in away from the system unit. The colour monitor requires a special adaptor in one of the expansion slots which supports up to 16 colours in text mode, up to four in medium resolution (320x200) and only black and white in high resolution (640x200).

It also allows you to define 128 graphics characters of your own. The board can also handle a light pen. To use your TV you'd have to buy an RF modulator.
The IBM monochrome monitor is a very high-quality 11.5in green phosphor device with an antiglare screen.

It gives a rock-steady display with no trace of flickering or that high-pitc hed whistling that sometimes occurs. The steadiness is achieved by using a high-persistence phosphor coating that takes a fraction of a second longer to clear than most screens, although I can think of one or two machines that are far, far worse.

Like this story? Spread the news by clicking below:

 del.icio.us     Digg this     reddit!