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Roland Huisman
December 12th, 2013, 01:25 AM
Hello everyone,

I've picked up an IBM 5150 for 25 euro (about 34 dollar).
It's complete with 5151 monitor and keyboard. And it even works!
Not a bad deal I think.

But... I'm a bit confused.

The case has 5150 as model number. The motherboard is a 5 slot 64...256Kb model.
The label at the front says 'IBM personal computer XT'. It's equipped
with an IBM badged WD25 harddisk and the well known Xebec controller card.
So it seems original to me.

But I thought the 'XT' was only for the 5160? Or am I wrong?

The man bought this machine new and it was his only computer.
So I don't think he has changed the cover with an other computer...

Regards, Roland

Ole Juul
December 12th, 2013, 01:55 AM
With a PC mother board I can't see it being called an XT. I wonder if the original seller was scamming. After all, having a harddrive, which was not so common on a PC, might be enough to satisfy some buyers that it was a newer model. I'm looking forward to some other comments here.

Stone
December 12th, 2013, 03:20 AM
Either one of the badges or the cover was replaced. Simply put, a 5150 PC ≠ a 5160 XT.

I guess it could have been a factory error like when the mint strikes a two-headed coin. But that would be impossible to substantiate today unless there are documents from the 1980s so indicating.

Trixter
December 12th, 2013, 10:43 AM
The man bought this machine new and it was his only computer.
So I don't think he has changed the cover with an other computer...


Then Occam's Razor applies: Whoever sold him the computer had swapped the covers prior to the sale.

If the person you got it from originally paid for an XT, then he was scammed. If not, then it might have been a simple mistake because the covers are identical except for the badge.

Chuck(G)
December 12th, 2013, 10:51 AM
That was my guess also--it's easy to do and I suspect that it may have been accidental.

SomeGuy
December 12th, 2013, 12:03 PM
A person working on it in the 80s or even 90s wouldn't have thought twice about accidentally swapping the cover with another or replacing a damaged one with a different one. Same deal with all the Apple II / II+ parts and revisions that are found intermixed.

pearce_jj
December 12th, 2013, 12:05 PM
Maybe the HDD was fitted by a store and the shop simply had a few on the go at the time. Any number of explanations.. but a very good buy for the money :D

barythrin
December 12th, 2013, 12:16 PM
Yup, great fine and great price! Any of those components could run ya that total most of the time. Always great to find complete systems for a nice price though for a collection.

Ole Juul
December 12th, 2013, 12:40 PM
A person working on it in the 80s or even 90s wouldn't have thought twice about accidentally swapping the cover with another or replacing a damaged one with a different one. Same deal with all the Apple II / II+ parts and revisions that are found intermixed.

Why is that? I'm an old fart who was an adult in those days and I wouldn't have thought twice about that. I don't think people's thinking processes were substantially different in the 80s and 90s. In fact that sounds hilarious when I think about it. :)

Anyway, I'm probably wrong about suggesting a scam. Stone nailed it when he said "Either one of the badges or the cover was replaced."

geoffm3
December 12th, 2013, 01:31 PM
That's a great deal on a 5150 or a 5160 IMO.

fatwizard
December 12th, 2013, 01:43 PM
Does the unit have the 63 Watt PC power supply, or is it the 130 watt an XT would have to power that hard drive? If it's the 63 watt job, then I would doubt it came from the factory like that. Maybe someone used a junked XT to upgrade the PC.

Roland Huisman
December 12th, 2013, 11:32 PM
Hello,

Thank you all for the replies. As I thought the combination of 5150 and XT is not correct indeed.
I will check if there are any dates in the machine and in the cover. I've seen date
stamps in other IBM machines.

Also the question from fatwizard about the power is a good one. I will check it tonight.
I think 63W is a bit poor to run such an WD25 full height hard disk.

Regards, Roland

billdeg
December 13th, 2013, 04:13 AM
I have seen a share of systems where a person upgraded their computer's insides at some point and as a touch style updated the sticker on the computer to reflect the change. For example, TRS 80 Model III's and 4. ALthough I doubt IBM officially supplied XT upgrade stickers, other manufacturers used to. For example Tandy memory upgrade by VRData, hard to see but they included a replacement sticker

http://vintagecomputer.net/tandy/TRS80_3_VRData/thm_TRS80ModIII_26-1061_wVRData_DiskIII_more.jpg

People were NEVER thinking oh, this will ruin the vintage computer collector value 30 years from now, I better not put the wrong sticker on my computer!

geoffm3
December 13th, 2013, 05:26 AM
Yesterday I checked on eBay and there were a couple of badges on there... one for the portable and one for an AT, so I imagine if OP wants one to be more correct then he should be able to get one fairly inexpensively (each were just a few $s).

SomeGuy
December 13th, 2013, 07:12 AM
Or slap an IBM Personal Computer badge on your new quad core. :)

I think some people may have went slappy happy with those things back in the day. For example this turned up on ebay: http://www.ebay.com/itm/IBM-Personal-Computer-AT-With-2-Hards-Drives-Beeps-/171179026255?pt=US_Vintage_Computers_Mainframes&hash=item27db10a74f#ht_3644wt_1040

It has an IBM badge, but aside from different buttons, that looks exactly like my JDR Microdevices clone case. This is why it is important to include pictures of a machine with the case off, and when possible a BIOS screen of the machine booting.

Tomn8tr
December 13th, 2013, 09:27 AM
Either the person selling the "AT" does not know their error, or they are bold to pull that one!

Tomn8tr
December 13th, 2013, 09:52 AM
Wow, I had nearly that same case back in the day. I made my own tags and sold a few of the machines. I think this photo was in 1987.
16323

Roland Huisman
December 13th, 2013, 12:00 PM
I've checked the dates. The main chassis is dated 24 oct 1986.
I think this is quite late for an 5150! And it could not be anything else
because the the label is on the 5 slot chassis.

The cover, monitor and keyboard are also dated 1986. Even the label on
the speaker holder is dated 1986. And it has an 150Watt power supply.
150W was probably quite normal for an 1986 dated machine?

I can't see any strange scratches or something like that around the label.
So it still can be a cover swap which has the same date stamp...

But I really wonder, could is be a left over which was updated by IBM
to an XT to sell it anyway? Maybe to get rid of old stock items?

Regards, Roland

SomeGuy
December 13th, 2013, 12:57 PM
I've checked the dates. The main chassis is dated 24 oct 1986.
Well, that is interesting. When exactly did they stop producing the 5150? Personally I find later/final produced systems interesting because they include all fixes and updates and sometimes (but not always) represent the "best" of a model. Do the part codes on the motherboard also jive with something made in 1986?

I doubt that "IBM" would have done something like that, but an end dealer, sure.

Roland Huisman
December 13th, 2013, 01:25 PM
Here some pictures. Chips soldered on the motherboard seem to be dated in 86 too.

1632516326163271632816329

Roland Huisman
December 13th, 2013, 01:30 PM
And some more pics....

1633016331163321633316334
(I've replaced the FDD drive)

Regards, Roland

fatwizard
December 13th, 2013, 08:27 PM
A beauty and a bargain, how ever it came to be (I'll bet a dealer did it too). Sweet!

Ole Juul
December 13th, 2013, 09:09 PM
When exactly did they stop producing the 5150?

The IBM 5150 was for sale from Wednesday, August 12, 1981 to Thursday, April 2, 1987.

Roland Huisman
December 14th, 2013, 01:17 AM
According the dates from Ole Juul, it seems to be one of the latest 5150s.

And as fatwizard says, a beauty and a bargain. I think the same.
Every machine has his (not always known) history. This label
has probably his own story.

But like I thought in the first place 5150 != XT.

Maybe I find a PC only label in the future. For now I really like the machine as it is.
I've had several 5160 machines but never had an 5150. And I definitely
want to play with that tape interface using Basic on an IBM.

Thank you all for your opinions.
Regards, Roland

per
December 14th, 2013, 09:06 AM
The WD25 HDD was mostly used in the XT-286 (IBM 5162) machines. There was a rumour that the XT-256 was designed just to get rid of the remaining stockpile of XT-chassises at the very end of the lifespan of the PC and XT. I doubt it, but in April 1987 the PS/2 line did completely replace the original IBM PC/XT/AT line so I won't deny they might have used what parts remained for the latest systems.

Practically speaking there are not much difference between the 256KB PC and the XT. The XT has more expansion slots and a motherboard with quite a bit of configuration posibilities*, while the PC has the casette interface. Otherwise they're practically identical.

* You can for example remove the BIOS from the memory-map with a jumper. Very convenient if you have a custom BIOS on an ISA card. There are also a lot of configurations for the motherboard memory decoding, with support for unusual memory chips (16Kx1b +5V only or 125Kx1b), or various onboard memory sizes. You can with a custom decoding chip practically map any of the onboard banks of RAM anywhere you want in the address space.

Ole Juul
December 14th, 2013, 12:49 PM
And as fatwizard says, a beauty and a bargain. I think the same.
Every machine has his (not always known) history. This label
has probably his own story.

I think the machine is just fine as it is, and the mystery of its past is actually a plus and part of its charm. Perhaps you can make up a likely story of your own about it. ;) As for collectability, there are plenty of factory perfect machines in collections. There are fewer that show the inevitable oddities of real life, like yours does.

BTW: Just for the sake of historical perspective, I believe the IBM XT came out, along with PC DOS 2.0, on March 8, 1983. The overlap with the ongoing production of the 5150 which had a long run, is noteworthy. Four years of having both side by side (more in practical presence) leaves a lot of room for some mixup.

Shadow Lord
December 15th, 2013, 11:50 AM
Well in case you want to "correct" it a badge just popped up (http://www.ebay.com/itm/IBM-Front-cover-BADGE-Metal-Plate-for-XT-AT-5155-Portable-case-/291038901595?pt=US_Vintage_Computing_Parts_Accesso ries&hash=item43c345355b)(not mine).

per
December 15th, 2013, 12:29 PM
Well in case you want to "correct" it a badge just popped up (http://www.ebay.com/itm/IBM-Front-cover-BADGE-Metal-Plate-for-XT-AT-5155-Portable-case-/291038901595?pt=US_Vintage_Computing_Parts_Accesso ries&hash=item43c345355b)(not mine).

That's for the 5155 portable.

Shadow Lord
December 15th, 2013, 12:32 PM
That's for the 5155 portable.

:blush: MY BAD! I looked at the small picture in the listing pages and just saw personal computer! DOH! Thanks for catching it per.

barythrin
December 16th, 2013, 07:37 AM
Actually that's a good point for anyone with a case and no guts or other parts unit although I don't think it's a major issue other than cosmetic and knowing yourself. If anything it's somewhat interesting if it was a professional fix, adds to the story of the system.

per
December 16th, 2013, 08:48 AM
One question I have. There is typically a date stamped somewhere inside the front cover. How well does it match the date of the main chassis?

SpidersWeb
December 16th, 2013, 10:19 AM
Just adding my experience, I have a 1987 5150, assembled in Australia, and the case badges are identical front and rear - "IBM 5150" instead of "Personal Computer". My 1987 5160 has the same traits, 5160 badge on the front instead of "Personal Computer XT".

I'm not sure if this was a marketing thing for the Australian/NZ market OR if IBM just started using one badge design instead of two in later batches.

vwestlife
December 16th, 2013, 05:52 PM
Just adding my experience, I have a 1987 5150, assembled in Australia, and the case badges are identical front and rear - "IBM 5150" instead of "Personal Computer". My 1987 5160 has the same traits, 5160 badge on the front instead of "Personal Computer XT".

I'm not sure if this was a marketing thing for the Australian/NZ market OR if IBM just started using one badge design instead of two in later batches.

My U.S. built PC manufactured in January 1986 says "IBM Personal Computer" on the front badge and "IBM 5150" on the rear badge. But I wouldn't be surprised if there were some creative substitutions being done at the very end of the production run, as they ran out of some parts and/or had excess inventory of other parts.

It surprises me that anyone would buy a 5150 after IBM effectively made it obsolete by introducing the floppy-only 5160 XT models in 1985, but I guess either the PC was still cheaper than the XT at that point, or some companies just wanted a real, original "IBM PC" and nothing else.

Denniske1976
December 19th, 2013, 01:58 AM
I picked up an XT yesterday that has the exact opposite :D

It's an XT, date labeled 24th sept 1985 in the case, with an XT 64-256K mainboard (8 slots) also labeled 1985, an ST-412 drive and one FH 360K drive and 130W PSU. The cover however, is labeled something octember 1986 and says "Personal COmputer" so it's the wrong cover hahaha. So my idea would be that these were switched during maintenance or something, since it also has a 3rd party memory card (probably upped the system to 640K, haven't powered it on yet because I'm still totally pulling it apart to clean the ages of dust and pine tree needles... yes, pine tree needles!).

geoffm3
December 19th, 2013, 06:03 AM
I picked up an XT yesterday that has the exact opposite :D

It's an XT, date labeled 24th sept 1985 in the case, with an XT 64-256K mainboard (8 slots) also labeled 1985, an ST-412 drive and one FH 360K drive and 130W PSU. The cover however, is labeled something octember 1986 and says "Personal COmputer" so it's the wrong cover hahaha. So my idea would be that these were switched during maintenance or something, since it also has a 3rd party memory card (probably upped the system to 640K, haven't powered it on yet because I'm still totally pulling it apart to clean the ages of dust and pine tree needles... yes, pine tree needles!).

Maybe you guys can work out a trade! ;)

simotion
February 20th, 2014, 12:55 AM
I had quite a few of these machines back in my youth, both the 5150 and the 5160... I also opened them up quite often to upgrade them, swap parts and what not. Who knows, I could have swapped the covers back in the day and my old machines eventualy ended up with you two... I never knew what exactly happened with my old baby's when my parents decided to end my collection while I was at school... I still wonder. So for comfort of thought I'm now going to asume you guys have them and they are still getting TLC, lol.

geoffm3
February 20th, 2014, 06:38 AM
When I worked at a computer store in the early-late 90's, it was SOP to take an old IBM PC case, rip the guts out and replace with a more modern motherboard and peripherals. It was also SOP to use a bit of this and a bit of that to make up a complete system since case parts and guts were mostly interchangeable. So, I would not be surprised to see many many mutts in the IBM PC's of today.

luvit
February 20th, 2014, 08:24 AM
if someone had two lids off of similar computers, it would be too easy for a lazy or greenhorn tech to confuse the lids.
this could have been a problem mistake since 1985.. lol.