seller says "tested working" if i had a dime for every time that isn't true. But ask the seller since he allegedly tested it. I have no idea but I guess that goes into some kinda backplane.

I asked him 3 days ago and he's yet to respond. Doubt it was tested in any way.

I feel like it probably goes into a backplane, but wouldn't a multiprocessor 8088 be cool?

I've came to the conclusion that this loop lies and lies and lie some more on all of his listings.

dorkbert wrote:

I've came to the conclusion that this loop lies and lies and lie some more on all of his listings.

All of them don't say "tested working" but most of them, so he just lies most of the time, 🤣

He has really good seller ratings and most of the stuff seems to be vintage computer hardware.

The store name "Bits Please" also seems to indicate that the seller is into computers.

And the stuff is sold as tested and working.. so if it isn't then you can get your money back.

I don't really see any reason to not believe that the seller is lying.

FAMICOMASTER wrote:

I saw this on eBay and TH99 has nothing on it: […]
Show full quote

I saw this on eBay and TH99 has nothing on it:

https://www.ebay.com/itm/CPU-Board-8088-Copro … -UAAOSwlf5ch~fT

It's an 8088-2 and an 8087 socket on an ISA board.

What is this? What is it used for? Is this like a multiprocessor option for an 8088? Would it support a V20?

This is what it says it is - CPU board from industrial computer (think of it like a reverse motherboard - instead of having a big PCB with CPU, logic chips and ISA slots - you have a card which you put into ISA backplane (which other than providing power to the CPU board and extension cards is passive and reliable) together with other cards). If stuff gets broken - you just _quickly_ replace single card instead of replacing motherboard. And being quick with repair is important on production lines and such... This stuff was costly (still is because many companies still operate old production lines or machine tools which were never modernized, because they are doing it's job just fine - from time to time I see people looking in panic for a very specific parts for their old machines). In desktop PC you would probably replace a single discrete component like CPU itself but stopped production can quickly lead to serious losses.

This part is a CPU board, containing a CPU (and FPU socket) plus everything needed to get it working and talking to other components, an EPROM (likely with a BIOS), maybe some RAM (though I can't zoom in on the pictures to clearly see the chips) a keyboard controller (and probably a pin header to connect a keyboard to), a speaker and what I assume is a reset button.
Boards like this would be inserted into a backplane supplying them with power and connecting them to other boards like drive controller cards, RAM cards, I/O controller cards and video cards. They're mostly found on industrial PCs.
They can not be used to create a multi processor system by sticking multiple cards on a single backplane. The 8088 isn't SMP capable.

I have some doubt the seller tested this card. Maybe he has the backplane to test it but maybe he's just hoping it works and going to refund your money in case it doesn't when a buyer tries to use it.

Edit: HanJammer beat me to it. 😁

Doornkaat wrote:

The 8088 isn't SMP capable

I would argue it doesn't really have to be SMP capable to work in multiprocessor system... in fact even basic 8088 + 8087 or 80286 + 80287 combos are MP systems - but not SMP - instead they are AMP.
286, 386 or 486 is by design not SMP capable as well (well at least not in the way more recent CPUs were/are), still there were multi CPU systems based on these CPUs - some were even SMP-like...
Sequent: https://en.wikipedia.org/wiki/Sequent_Computer_Systems
ALR: The ALR Powerpro: - Dual 386 EISA System
Compaq: https://en.wikipedia.org/wiki/Compaq_SystemPro
Intel iPSC multi-286 supercomputer: https://en.wikipedia.org/wiki/Intel_iPSC
Interesting read: https://books.google.pl/books?id=tzAEAAAAMBAJ … epage&q&f=false

HanJammer wrote:

I would argue it doesn't really have to be SMP capable to work in multiprocessor system... in fact even basic 8088 + 8087 or 802 […]
Show full quote

Doornkaat wrote:

The 8088 isn't SMP capable

I would argue it doesn't really have to be SMP capable to work in multiprocessor system... in fact even basic 8088 + 8087 or 80286 + 80287 combos are MP systems - but not SMP - instead they are AMP.
286, 386 or 486 is by design not SMP capable as well (well at least not in the way more recent CPUs were/are), still there were multi CPU systems based on these CPUs - some were even SMP-like...
Sequent: https://en.wikipedia.org/wiki/Sequent_Computer_Systems
ALR: The ALR Powerpro: - Dual 386 EISA System
Compaq: https://en.wikipedia.org/wiki/Compaq_SystemPro
Intel iPSC multi-286 supercomputer: https://en.wikipedia.org/wiki/Intel_iPSC
Interesting read: https://books.google.pl/books?id=tzAEAAAAMBAJ … epage&q&f=false

Agreed. But cards like the one posted that incorporate their own BIOS and keyboard controller are simply not made to do that.
You could probably even build a main controller to assign work to multiple CPU cards and build a computing cluster but this card is designed to be put into a "dumb" backplane that simply connects it with other cards. It's not meant to upgrade an existing 8088 to a dual CPU machine. That's what I think FAMICOMASTER was trying to ask. 😀

Doornkaat wrote:

It's not meant to upgrade an existing 8088 to a dual CPU machine. That's what I think FAMICOMASTER was trying to ask. 😀

Well, I've been referring to your statement which concerned 8088 and not this particular card (which surely, is not designed for this purpose)...

Probably it's a CPU card for one of these Zenith PC clones that had a backplane instead of a motherboard.

Yeah, I figured it was for a backplane.

But it would still certainly be interesting to have a dual-8088 machine.

HanJammer wrote:

Well, I've been referring to your statement which concerned 8088 and not this particular card (which surely, is not designed for this purpose)...

I'm not sure what statement you're referring to. 😕
I was trying to say that simply connecting another 8088 to the PC/PC XT system bus isn't possible because the CPU isn't SMP capable. They'd have to share the same adress space but they can't.
You'd have to design a different computer to run two 8088 in the same computer.
Or am I totally wrong here? I certainly don't think that's impossible. 🤣

Doornkaat wrote:

HanJammer wrote:

Well, I've been referring to your statement which concerned 8088 and not this particular card (which surely, is not designed for this purpose)...

I'm not sure what statement you're referring to. 😕

The one I quoted above:

Doornkaat wrote:

The 8088 isn't SMP capable

I'm just saying that it's not really the case as he wasn't referring to SMP architecture at all (which is just a subset of the "multiprocessor option" he was referring to) 😀

I think now I get it.
You can make a multi processor system without needing CPUs with SMP support. Totally agreed. 😀

Edit: I really like what you did with the colours in your signature btw. 😲