Artifact of the Month: IBM Personal Computer AT, ca. 1984

Our May Artifact of the Month is the state-of-the-art IBM Personal Computer AT, IBM’s second-generation PC.


While this computer may seem like a mammoth in comparison to the latest MacBook Air, it was IBM’s streamlined and state-of-the-art release in August of 1984. In fact, AT stands for Advanced Technology. Advanced, high-technology features of this computer include: 80286-based processor with 265k RAM, one 1.2-Mbyte floppy disk, and high-capacity diskette and fixed-disk drives. When it first went on sale, all this and more could be had for the low, low price of $3,995!

If the RAM-and-bytes jargon doesn’t make sense to you, we’ll simplify: this computer was pretty high-tech for its time, and it was designed for professional applications, office environments, and personal productivity. This computer in particular was used in an office in Davis Library during the first decades of automated record keeping and online searching.


To put technology growth into perspective: In August of 1984, the IBM Personal Computer AT was released with a memory capacity of 256K RAM. In 1995, the average RAM of most computers was 2 Megabytes. Modern-day RAM is anywhere between 4-12 Gigabytes. In other words, from 1984 to 2016 there was a million-fold increase in computer memory capacity. That’s pretty astounding.

UNC has close ties to IBM because of Fred Brooks, computer architect and founder of UNC’s Computer Science department. Brooks managed the development of IBM’s System/360 family of computers that revolutionized IBM computing, made advancements in capability, and allowed machines to be upward-compatible. Brooks also facilitated the transition of the 360-series from a 6-bit byte to an 8-bit byte. Simply put, a byte is the number of bits used to encode a single character of text in a computer, and for that reason it’s the smallest addressable unit of memory in computers. The switch from a byte composed of 6 bits to that of 8 bits allows us to use lowercase letters.

If, like us, you’re thankful that computer text is not all caps and doesn’t read as if someone is yelling at you, give Fred Brooks a nod if you ever see him on campus.