27 Oct
2001
27 Oct
'01
12:52 p.m.
I was hired to worry those matters. Nevertheless,
I've got a '386 motherboard
sitting downstairs somewhere that uses a '287 rather than the usual '387. I
Confirmed, I had one and soon became flaky. Was 386DX 25 baby AT w/
socket for 387 or 287, based on 386dx C&T (yeech!) chipset, no
support for cache, black and white AMI screen. Yes it existed.
didn't buy it for that reason, but I did keep it
for that reason. If I'd gotten
enough documentation to explain what was going on, I'd have more info for you,
but with the PC-"standard" falling apart with the release of the '386,
because
IBM no longer provided a firm ISA-equipped standard that everyone else could
clone, there was nothing but chaos, and that's the way it's been ever since.
The whole concept of "standard" was corrupted in the course of this
evolutionary
step, and it was a step into the quagmire we're all swimming in today.
Bit better now for last few years. 91-95 was the worst years.
BTW, if that "bulky old PSU" still works,
I'd happily relieve you of the fan and
PSU board, and pay you for the freight, except for where you're located. I find
Exactly, I did this to extract decent fans from them. Few days ago
swapped ATX windy noises has that noise killer sticker yeah right!
For quieter fan.
The ISA Ram will run at the ISA rate, which is not
terribly fast, but it's
normally as fast as the CPU requires. Unfortunately, the ISA clock is a
STANDARD, at 8 MHz, so, even in cases where the CPU runs at 10 or 12 MHz, (I've
got one that runs at 24), the ISA is still limited by that 8 MHz clock.
Not usually, junky clones had odd ISA clocks and some were too high.
Dick
Wizard