One of the comments suggested that “XT” machines used the 8088 and any machine that used an 8086 would be an “AT” machine since it was a “x86” variant. I disagree with that understanding of what is an XT and what is an AT.
If you are younger than 50 you may not remember the days of the IBM PC, then the XT, and then the AT. I was just entering the work force in the 80’s and by 1989 I was looking to buy my first “personal computer” that I would use in our small family business.
I was aware of the IBM PC in 1981, as was my yet-to-be father-in-law. But the system that was chosen by my father-in-law’s family for their business was a NorthStar Advantage. I married into that family in 1987. By that time my FIL had moved the Advantage into the attic and was using his IBM PC. I was involved in upgrading that IBM PC machine with a Hercules graphics card and a 20MB MFM hard drive. This effectively turned his PC into an “XT”, although we still had the original motherboard/planer so it was not a “real” XT.
In the late 80’s and into the early 90’s I was carefully considering what would be my first personal computer that I would buy with my own money. As I remember it, an “XT class” machine was either the actual IBM XT or a “clone” of the IBM PC/XT class of machine and it almost always came with an 8088. Sometimes an XT Clone was offered with a V20/V30 replacement for the 8088/8086. But an XT was always cheaper than an “AT Class” machine and it was being offered as an alternative to the IBM AT and AT Clones which were much more expensive.
The original IBM AT was using an 80286. It was “advanced technology” over the previous PC and XT classes. When looking at alternatives to the IBM AT we looked at machines with 80286 processors. At least in our market (Northeast US) an “AT” clone was using an 80286 - NOT an 8086. An 8086 was always considered as an XT Class.
When IBM introduced the PS/2 line that replaced the previous lines (PC/XT/AT) they did offer a couple of models that used an 8086 and an ISA bus. We considered this a substitute for an XT rather than an AT. It was an offering that allowed users who didn’t want to upgrade to the AT/80286 or MicroChannel to stay with their PC/XT software and save some money.
As a buyer at that time I considered 8088 and 8086 as XT Class. I considered the 80286 as AT Class. I did not know that Tandy would later use some 80286 processors in some of their XT Class machines. I was also not aware of some of the European machines that were using the 8086 instead of the 8088. But I understood that the 8088 was essentially the same as the 8086 only it was using an 8-bit external bus. The 80286 was a different animal and was the next generation being used by IBM in their advanced technology ATs.
As to the popularity of these two classes among the DIY system builders at that time, my recollection is that kit builders and hobbyists of the day were much more likely to be building on some other platform like a 6502 or Z80, etc. And gamers were usually more interested in Commodore and Atari than PC Clones. But as PC Clones became more common as personal, or home computers, it was very common, at least in my circles (which was about business use and we were not gamers), to purchase “Bare Bones” systems and build up from there. If you did not have the knowledge to DIY you would go to a local computer store and they would build you a “white box”.
You would buy a bare bones system that would include a case and power supply, either an XT class MB or an AT class MB, and a keyboard. Then you would add your monitor and video card (sometimes already integrated into the MB), RAM chips, floppy and hard drives, and maybe a multi-I/O controller (sometimes already integrated even in XT class machines). Actual IBM AT and PS/2 machines were expensive but many business people like us purchased them because they felt more comfortable with IBM and did not like the idea of DIY. But eventually the clones did become popular with the DIY and gamers. But I do not remember this being very common with XT and AT class machines. I remember the build your own movement being more around the time of the 80486 and Pentium and then AMD.
Seaken
