Re:The 640K memory limit of MS-DOS
by bitwize on Saturday June 09, 2018 @08:32PM
(#17275776)
It's amazing to think how hamstrung the early PC was by stuff like the 640 KiB limit.
The contemporary Tandy 2000 could be kitted out with up to 768 KiB of memory (896 KiB with an aftermarket add-on). Because it loaded its BIOS from disk instead of having it in ROM, and because there were no hardware restrictions on contiguous access to memory except perhaps the video framebuffer, the Tandy 2000 could use nearly all that RAM, and was for a brief shining moment preferable to the IBM PC, XT, or AT for memory-intensive jobs like Lotus spreadsheets. That and its hi-res color display made it sought after as an inexpensive CAD workstation.
It was not 100% PC compatible, but PC business apps often needed only a few small patches to work on the 2000, so official and unofficial ports were available.
The contemporary Tandy 2000 could be kitted out with up to 768 KiB of memory (896 KiB with an aftermarket add-on). Because it loaded its BIOS from disk instead of having it in ROM, and because there were no hardware restrictions on contiguous access to memory except perhaps the video framebuffer, the Tandy 2000 could use nearly all that RAM, and was for a brief shining moment preferable to the IBM PC, XT, or AT for memory-intensive jobs like Lotus spreadsheets. That and its hi-res color display made it sought after as an inexpensive CAD workstation.
It was not 100% PC compatible, but PC business apps often needed only a few small patches to work on the 2000, so official and unofficial ports were available.