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IBM 5150 possible inconsistency?

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New2vtgpc

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So...I couldnt stop myself and picked up an iconic ibm pc 5150. Its in rough shape and found a lot of nasty things inside the case, including dead mouse and lot of corrosion.
So while mid restore...i found a few inconsistency with what limit knowledge I have on the machine. 1 is that is has a monochrome card with parallel port which is fine but theres also a a card with thr female parallel, which is odd theres 2.
2 is the psu...its labeled 63.5w, which makes sense with the hard drive controller card...but board is stamped 64k-256k which would be rev2 and the bios chips are labeled 1983 which would make it rev3...amd the psu screws were loose on the case.
The bios chips leads me to believe its a late revision and can let a xt-cf card and a vga card to use it....
But the small psu tells me its a first revision since rev2 and 3 had higher watt for an optional internal hd, which makes the hd controller a normal thing but not with the higher on board ram AND bios dates...
Any ideas? (Oh and any help on mods/upgrades, ideal software to put on this IF a xt2cf is possible)
 
Could you post a picture of the second card? It might be a SCSI card, some of which came with 25-pin external connectors identical to a parallel port. Two parallel ports isn't impossible if the system was used as a print server or for one of the cheap networking setups.

5150s normally weren't shipped with the higher wattage power supply of the XT so it isn't impossible to get the same power supply as the original 5150s.
 
Every unmolested 5150 I’ve ever seen had a 63 watt power supply. So far as I’m aware it was standard equipment right up to the end.
 
I recently picked up two of the later B models with silver power supplies and 64-256K boards. One is floppies only and has the 63.5 watt power supply and one was upgraded at some point with lots of extras like a hard drive, EGA, etc, and has an aftermarket 165 watt power supply.
 
Eudimorphodon said:
Every unmolested 5150 I’ve ever seen had a 63 watt power supply. So far as I’m aware it was standard equipment right up to the end.
Click to expand...

I wasnt sure on the psu thing. I know the xt had higher watt ones for hd and I *thought* I read somewhere that later revision 5150 had optional higher watt one for a possible hd but not certain..i probably wrong.
 
New2vtgpc said:
So...I couldnt stop myself and picked up an iconic ibm pc 5150.
Click to expand...
New2vtgpc said:
So while mid restore...i found a few inconsistency with what limit knowledge I have on the machine.
Click to expand...
Lots of IBM 5150 information at minuszerodegrees.net

New2vtgpc said:
1 is that is has a monochrome card with parallel port which is fine but theres also a a card with thr female parallel, which is odd theres 2.
Click to expand...
If I go to the rear of one of my 5150's, I see two 25-pin parallel ports. One is provided by the IBM MDA card. The other is provided via an 'IBM Printer Adapter' card. Per [here], they can co-exist.

Why two? Some examples:
1. Two printers.
2. A parallel port based security dongle/key is interfering with printer operation (it is not meant to) and so it gets put onto its own parallel port.
 
jafir said:
I recently picked up two of the later B models with silver power supplies and 64-256K boards. One is floppies only and has the 63.5 watt power supply and one was upgraded at some point with lots of extras like a hard drive, EGA, etc, and has an aftermarket 165 watt power supply.
Click to expand...

I'm hoping mines a later reviosn for ega/vga and an cf adapter. The psu im not worried about since I'm not planning on trying to fit a vintage hd, but just thought the low watt was off. Learning it might be normal lol
 
New2vtgpc said:
I *thought* I read somewhere that later revision 5150 had optional higher watt one for a possible hd but not certain.
Click to expand...

Standard advice back in the day was to *replace* the PSU if you added a hard drive to the 5150, but so far as I'm aware IBM never sold one with either a hard drive or the bigger PSU.

(They would sell you that external expansion chassis that looked like a PC with no drive bays if you *really* wanted a 5150 and a hard drive, but they never made it an internal option, that's what the 5160 was for.)

Of course, for a while I had a ridonkulously tricked out 5150 with a full height 10MB IBM hard drive, an EGA card, *and* the original PSU, but I don't imagine I'd actually *recommend* that.
 
Eudimorphodon said:
Every unmolested 5150 I’ve ever seen had a 63 watt power supply. So far as I’m aware it was standard equipment right up to the end.
Click to expand...

That may have been true for America, but didn't European 5150 PSUs all have more watts by default? Correct me if I'm wrong. I know at least some did.
 
ropersonline said:
That may have been true for America, but didn't European 5150 PSUs all have more watts by default? Correct me if I'm wrong. I know at least some did.
Click to expand...
No. Have one from early 1985 made for Germany and it has the same 63 watt PSU as all others.

PC090668.jpg
 
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Eudimorphodon said:
Standard advice back in the day was to *replace* the PSU if you added a hard drive to the 5150, but so far as I'm aware IBM never sold one with either a hard drive or the bigger PSU.

(They would sell you that external expansion chassis that looked like a PC with no drive bays if you *really* wanted a 5150 and a hard drive, but they never made it an internal option, that's what the 5160 was for.)

Of course, for a while I had a ridonkulously tricked out 5150 with a full height 10MB IBM hard drive, an EGA card, *and* the original PSU, but I don't imagine I'd actually *recommend* that.
Click to expand...

Maybe thats what i read...or that people swapped in an aftermarket psu. Either way, i dont plan on finding an external hd for this since it was hard enough finding this relic...
And nice job getting an hd to work with the oe supply...im guessing you strained it a bit at times?
 
New2vtgpc said:
Maybe thats what i read...or that people swapped in an aftermarket psu. Either way, i dont plan on finding an external hd for this since it was hard enough finding this relic...
And nice job getting an hd to work with the oe supply...im guessing you strained it a bit at times?
Click to expand...
AFAIK the need to upgrade the PSU was if you intended to use one of the original full height drives that was supplied with the XT at first due to the load the spindle motor would put on the supply.

I'm sure the OEM supply was fine with later half height drives which ended up being supplied with late XTs, and it's certainly fine with newer IDE drives - I have a 3.5" IDE drive squashed into my 5150 running off an XTIDE and it's fine with the original power supply.
 
maxtherabbit said:
OP, what floppy drives did yours come with? Tandon, MPI, CDC, etc.
Click to expand...

No idea yet...im tackling the mainboard first, getting the chips off and cleaning rust and corrosion of everything before i get into the drives. They have the ibm branding and identical at thr moment
 
cwathen said:
AFAIK the need to upgrade the PSU was if you intended to use one of the original full height drives that was supplied with the XT at first due to the load the spindle motor would put on the supply.

I'm sure the OEM supply was fine with later half height drives which ended up being supplied with late XTs, and it's certainly fine with newer IDE drives - I have a 3.5" IDE drive squashed into my 5150 running off an XTIDE and it's fine with the original power supply.
Click to expand...

Yea I can imagine those early double height being power hogs, hopefully my board accepts xtide cards...cause a hdd would be super useful if the floppies bad
 
Timo W. said:
ropersonline said:
didn't European 5150 PSUs all have more watts by default? Correct me if I'm wrong. I know at least some did.
Click to expand...
No. Have one from early 1985 made for Germany and it has the same 63 watt PSU as all others.
Click to expand...

That's odd. So you mean all the 5150s sold in Germany were 63W or all the ones all over Europe too? Would there have been a difference between the ones made for and sold in certain parts of Europe as opposed to others? Specifically, does anyone know if UK 5150s in general had slightly beefier PSUs? Maybe the UK-provenance machine I'm thinking of had its PSU upgraded on the sly – but it had always been my belief that at least some of the 1983+ non-American 5150s had had slightly better PSUs from the start. Does anyone have authoritative info on this?
 
ropersonline said:
That's odd. So you mean all the 5150s sold in Germany were 63W or all the ones all over Europe too? Would there have been a difference between the ones made for and sold in certain parts of Europe as opposed to others? Specifically, does anyone know if UK 5150s in general had slightly beefier PSUs? Maybe the UK-provenance machine I'm thinking of had its PSU upgraded on the sly – but it had always been my belief that at least some of the 1983+ non-American 5150s had had slightly better PSUs from the start. Does anyone have authoritative info on this?
Click to expand...

Unless you have some authoritative proof that the PSU in the machine you're thinking of *wasn't* swapped out, well, lacking any specific literature for a specific market that says otherwise the April 1984 edition of the IBM 5150 Technical Manual lists two possible power supplies for that machine, a 120v one and a 220/240v model, and both have a rated capacity of 63.5 watts.

That said, here's the deal I remember with those machines: although the 63.5 watt rating was consistent the "quality" of the power supplies in the 5150 varied a lot over the production run of the machine. I vaguely recall magazine articles complaining that the stock power supply had a bad habit of blowing up even in a relatively bare and unexpanded machine, while other people said they had no problem filling all the slots with upgrades and even slapping a hard disk in. (I never noticed any issues with my ridiculously overexpanded 5150's power supply, but that was probably just dumb luck. I in fact specifically left the 63 watt PSU in it out of curiosity to see if it could take it; at the time a whole 5150 or 5160 cost about $10 from the local government surplus outlet store so it's not like I cared a lot if I melted it.)

Since the PSUs are physically compatible I certainly wouldn't rule out that even IBM repair centers might have substituted 5160 power supplies at their discretion, so even you knew for sure that the power supply in this unit you're thinking of was in fact an IBM unit and had in fact been installed by "IBM" that still doesn't prove that there was an official "alternate spec".
 
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