>>>>>Are you saying that apps that I've written on my XP with AMD processor will not work on an Intel Win10 pc?
>>>>>Rich
>>>>
>>>>No, that's not what I say. AMD CPU's are Intel-compatible, what Microsoft calls "Intel type", so you don't have to worry.
>>>
>>>The x86-64 instruction set (commonly called AMD64 by many entities other than Intel) was created by AMD, not Intel.
>>>
>>>So, Intel CPUs are AMD-compatible ;)
>>
>>not debating your statement, but as vfp is only 32 bit, only the part on the left of the hyphen is important ;-))
>
>When was the last time it was possible to buy a Windows computer that was not x86-64 capable? ;)
>
>>Although I am pretty certain that vfp6 and higher cannot be made to run on an Intel 8086, guessing at least 80386 instruction set is neccessary, which would imply 80386SX as lower bound ;-)
>
>The 386SX could theoretically address up to 16MB RAM so might meet lower bound for W95 or W98. However, it was a budget chip and ISTR a lot of 386SX mobos were limited to 2MB RAM. W95 minimum RAM (per MS) was 4MB: https://support.microsoft.com/en-us/kb/138349 . That was back in the days when MS "minimum" figures were so low that you had to double them to get a system that was usably fast and didn't crash once per hour when running more than 1 program at a time.

IIRC it was possible to install Win95 on a 386SX system (at least on the beta release) -- one of my friends did this as en experiment (the machine was as close to the minimum specification as possible). Time from hitting power switch to signon screen was enough for him and a group of his co-workers to go out and get a bite to eat -- the signon screen was just coming up when they returned. I do remember trying out Win95 on a 33Mhz 486DX system with 8MB RAM -- booting from DOS 6.2 (w/ McAfee Antivrius), then manually typing "win" to start Windows 3.1 ended up being faster on a similar computer with 33MHz 486DX w/ 4MB RAM.