OT: Good place to ask about XP memory problems

[Andy Champ]

Wasn't that a '386 jammed down a narrow bus?

Andy

[Clive George]

And it's not portable anyway...

[The Natural Philosopher]

386sx pretty good chip actually. cheap and just about ran whatever windows it was then..3.1?

bought tens of machines using those.

[The Natural Philosopher]

more or less yes.

8 bit data bus, but 32 bit internals.

[The Natural Philosopher]

messagenews:j88irg$qvd$ [e-mail]...

well, exactly.

Reading between the lines dennis grew up big endian, found a little endian chip and pissed his pants.

[Jules Richardson]

16-bit I think, not 8.

Then it got confusing because in the later 486 era the SX suffix was used to denote the absence of the floating-point hardware, not a variant with a narrow bus...

[dennis]

You mean don't use C.

The only reason it looks portable is the pruning of hardware. If everything looks like a PC its portable.

[dennis]

Endianism isn't the biggest problem.

[The Natural Philosopher]

Yep..you are right.

cant remember 486sxes..must have skipped to a pentium.

[John Williamson]

Then there was the 486DX line, which used an internal clock mulitplier for the processor.

[Clive George]

DX2 and DX4, with x2 and x3 multipliers. DX was the non-multiplied one with FP, SX without FP.

[Bob Eager]

Well, not quite. Just a narrower bus; programming-wise, identical. A bit like the 8086/8088, 80186/80188, 80286/80288.

Not that many even know about the 80188 and the 80288...

[Bob Eager]

Basically only 4kB directly addressable. And, until XA, maximum address space of 16MB.

Indeed, the 2900 is a very clean architecture (well, after they changed it a bit, a year after we got the machine).

[Bob Eager]

Which was only true before Windows NT.

[Bob Eager]

V20 == 8088 V30 == 8086

(but with extras, as you say). I have the technical manual here somewhere.

[Bob Eager]

Maybe not for you.

[Bob Eager]

And only 16MB addressable, even physically, as I recall.

[Bob Eager]

No, that was the DX2. The DX was the 'standard' 486 with the FPU included.

[Bob Eager]

And the other has superfluous quotes.

[Jules Richardson]

I've seen quite a few '188 processors used at the heart of things like disk and network controllers in larger machines of that era - I think that's the first time I've ever even seen mention of a '288, though. Was it essentially a '286 with a narrow bus interface (just as the '188 was to the '186)?

Google's not really coughing up anything useful (other than some speculation that it might not actually have existed :-)

cheers

Jules