The Altair 8800 is arguably the computer that sparked the microcomputer and ultimately the home computer revolution. It was originally designed in 1974 and gained massive popularity in 1975 and beyond. The Altair 8800 was responsible for the S-100 bus, an expansion bus (pre-ISA) that was popular in the CP/M based computers that were popular in the late 1970s and early 1980s.
The Altair 8800 featured the Intel 8080 CPU, an 8-bit CPU running at 2 MHz. The Altair could be ordered as a kit or fully assembled but assembly added almost 50% to the price. And you couldn't expect much for your $439 outlay...even the memory had to be purchased separately. 1 KB, 2 KB and 4 KB memory cards were available with a total of 8K being a desirable amount if you could afford it. If you wanted any software then you had to be prepared to pay extra...a lot extra. In addition, what we are really talking about is not ready to use software but tools to use to create your own software. For example, BASIC would set you back $350 to $750 depending on the version you purchased though this would be discounted with additional hardware purchases. And unless you bought a terminal with keyboard for another $780 to $920 then be prepared to program your new computer by flipping switches. When ordering software you had to specify whether you wanted that on paper tape or cassette tape.
Keep in mind the prices above are 1975 dollars. In today's dollars (after inflation) just the basic computer kit with 1K of RAM would run you around $3000 assembled. If you wanted something that resembles a modern computer today then you are talking many thousands more in today's dollars. However, the Altair 8800 was perhaps the first commercially available microcomputer to have strong 3rd part hardware support so there were at least some somewhat cheaper options available when it came to expansion. Early adopters were stuck with flipping switches and looking at lights. If you wanted interest free financing then MITS was there to help...provided you didn't mind getting your new computer one piece at a time.
The ad above is from the November 1975 issue of Byte magazine.
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