IBM 5150 maximum memory?

Roy J. Tellason rtellason at
Thu Apr 24 15:06:27 CDT 2008

On Thursday 24 April 2008 15:50, Jules Richardson wrote:
> Roy J. Tellason wrote:
> > On Thursday 24 April 2008 14:45, Jules Richardson wrote:
> >> But yes, fair point about the expansion boards. I expect it was unusual
> >> to see a 5150 without floppy drives, and I don't think the things would
> >> even boot without a display adapter (something that's plagued server PCs
> >> ever since!)
> >
> > Heh.  I have one machine (the firewall/router) that's built around a 486
> > board that although it does indeed have a monitor attached it's almost
> > never turned on.  I can see the utility of some boxes here that wouldn't
> > even have a monitor attached at all,  too.
> Well, it goes beyond that - what's the point of having the video circuitry
> there at all if your access to the system is always via serial, network, or
> some other 'remote' means. The problem was that the PC was designed as a
> single-user workstation, and no thought was ever given to server mentality
> (no fault of IBM at the PC's launch - it's just a shame that every modern
> machine I've tried still needs a video card installed and running, even if
> I don't actually use it)

Yeah,  I haven't found one yet that won't complain with beep codes if you 
leave it out.  I guess one that has stuff on the MB might be least intrusive 
if you don't plan to use it,  but still...

> > (Snip)
> >>> The company I worked for at the time bought a PC on the day of release
> >>> (August 12, 1981), specifically to develop third-party peripherals and
> >>> software.  The company was one of the first to market with a "combo
> >>> card", but was never as successful with it as AST, Quadram, etc.
> >>
> >> I wonder how many such vendors there were? Every (IBM) PC I've ever
> >> looked in seems to have a different multi-function board from a
> >> different vendor in :) (and of course the documentation on how to set it
> >> up is long gone)
> >
> > I have actually a bunch of those old boards around _and_ docs for them, 
> > if somebody needs some help with that,  either in terms of taknig some of
> > that old hardware off my hands or getting something working.
> I'd actually quite like to get hold of a 5160 on this side of the pond
> sometime, whether it was stuffed with IBM boards or not (actually, I think
> I still have a few boxed IBM memory and display boards in storage back in
> the UK - just nothing to put them in :-)
> Shipping such a beastie even within the US would be a nightmare though,
> plus I'd be reluctant to leave a ST506/412 drive at the mercy of a shipping
> company (I'm really not looking forward to getting the ones I do have in
> machines back in the UK across the pond).
> Maybe I should publish a wish list sometime and see what I can line up to
> buy from people at one of the VCFs :-)

I was referring more to plug-in boards and not whole systems,  but I might 
have some of those around too.  :-)

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be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet Masters"
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M Dakin

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