Jo22 wrote:So in theory, the DX could also run in "386SX mode" on a 286 or 386SX chipset, couldn't it ? 😀
In theory yes, because that's exactly what a 386SX is (just like an 8088 is an 8086 on an 8-bit bus).
Jo22 wrote:If so, this would explain why the press in old PC magazines (~mid-late 80s) described the 386SX as "lame":
At least the original, non-enhanced SX (386SX-16) is/was just a pin-reduced version of the normal 386.
Yes... Technically the real 386DX-16 was pretty 'lame' already. The early 386 systems weren't all that much faster than equally clocked 286s.
Check this out for example: https://books.google.nl/books?id=nuXmVNll5JEC … c%20mag&f=false
The true power of the 386DX only came later, firstly, because the clockspeeds were ramped up to 33 MHz (I suppose the 386DX-33 is the 'archetypal' 386DX, much like the 486DX2-66 is for the 486). Secondly, because 32-bit software arrived, taking advantage of the new features of the CPU. And thirdly, because motherboards and chipsets improved, and caches were added to 386 machines.
And 386SX machines were actually slightly slower than equally clocked 286 machines at the same clockspeed.
The 386SX however, remained a budget machine. It basically ran on modified 286 motherboards, was always limited to a 16-bit bus, so 32-bit software didn't gain all that much. And because it was a budget solution, the motherboards generally didn't have cache either, and the clockspeeds were low (The 386SX-16 is probably the 'archetypal' 386SX, even though SX models up to 33 and 40 MHz do exist).
So over time, the gap between the SX and the DX grew bigger. Both in actual performance at the same clockspeed, and also in perceived status, because DX were high-end systems, and SX were low-end systems.