The IBM 5100 was released in 1975, which was based on the 1973 IBM SCAMP project [video]. This was a “portable” data-processing workstation that included a tape cassette storage, up to 64KB RAM, supported both BASIC and APL programming, with a 5″ CRT screen and integrated keyboard. This was all available in 1975, the same year as the Altair 8800 kit. While the Altair kit was around $500 (with no keyboard or monitor or storage device), the IBM 5100 was priced about $20,000 (in 1975 dollars) as a ready-to-go product.
In 1978, IBM released an updated version called the 5110: the tape cassette interface was no longer standard (an external tape or floppy disk drive were offered options with the new external I/O interface port), either APL or BASIC (or both) could be ordered. But the same “A1″ motherboard, PALM processor, power supply, and 5” screen as the 5100 were used. The base price of the 5110 was around $11,000. One cosmetic difference was that the 5110 has a black front face around the keyboard, whereas the 5100 has white.
The 5110 described within these articles has a date markings inside indicating it completed assembly around July 1979.