IBM 5150 saved from junkyard

[phonophan]

Hello!

New user, first post... thank you, in advance for reading!

I came a cross a "FREE" craigslist posting for an old computer. I wasn't sure exactly what it was from the listing... but I picked it up today - he explained that he was the original owner and that he didn't want it going to the junkyard.

All in all, this is what he gave me:

- IBM 5150 Personal Computer
- IBM 5151 monitor
- PGS SR-12 monitor
- IBM Personal computer keyboard
- Epson MX80IIIF/T

It's been quite some time since dealing with something this old... so here are my initial results... I can turn it on and it boots to IBM PC-DOS. I can boot MS-DOS 2.0 from the A: ... the B: also will read disks ... so the computer appears to be in good working condition.

I guess some questions...

1) He mentioned this has been upgraded from factory specs... can help me identify what the cards are in the expansions? What is factory and what is added on? ...and what to they do?

2) One of the expansion cards has a ribbon and a port ... that there appears to be no room for... he just had the ribbon literally hanging out of the case. Any advice?

3) The IBM 5151 monitor powers on... but at most all I will see (by adjusting the knobs) is a green box running down the center of the screen. Any advice? The PGS SR-12 is working.

4) What's would be the most I can do on this thing... in terms of programs / games?

All in all, i'm having a blast on this and am thrilled it is not in a junkyard. Again... thank you for your time and help!

Pictures attached.

IMG_1069.jpgIMG_1068.jpgIMG_1067.jpg

[SpidersWeb]

1)
Well it has CGA and MDA installed, so you can run dual monitors if you wish
I don't know what the pass through card on CGA side of things is, text overlays on the CGA output perhaps?
Also a typical multi-function card, that the floppy drives are plugging in to, adds RAM and various ports. Common upgrade as it puts multiple features in a single slot.

2) looks like they had to remove it in order to fit that magic video card thing that piggybacks off the CGA card. Make sure to keep it, black brackets are rare.
You don't actually need the port though, since the MDA card has a parallel port anyway.

3) There is two video ports, make sure the 5151 is connected to the port above the DB25 parallel port, and not the one with composite video. In DOS you can type "MODE MONO" and you should see a prompt.
Switches on the motherboard will define which card starts first - MDA or CGA. If it's plugged in correctly and still does that, then damn, may need a fix.

4) depends on how patient you are and what you want, some people push them to their limits and even install CPU upgrade cards, for me I try to find software made before ~1987 because that's usually going to work well off a floppy disk and with a 4.77Mhz CPU. I know one of mine had a hard drive and Windows 2.11 with AmiPro (first Windows based WYSIWYG document editor that I'm aware of) - very painful - but somebody was using this!

p.s. you scored well, that appears to be the early version, known as the "Model A" unofficially. Hence the wider black expansion cards, which were changed to thinner silver ones in 1983.
To confirm, check the motherboard, if it says 16-64K SYSTEM BOARD, then you win.

People giving better advice will likely reply after me, but thought I'd quickly pass on my two cents.

[lafos]

If you can pull the cards and take pictures of the component sides showing any markings, it would help to identify them. A photo of the motherboard without the cards would also be nice to see.

Just make sure that the computer is disconnected from AC power before. Also, make notes of what went where so you can fit it all back in.

[phonophan]

Thank you for the quick and kind responses!

I had plugged the 5151 into the wrong monitor port - unfortunately, when plugged into the other port... I got nothing... not even a green box.

Separately... I have pulled all the cards and photographed them and the motherboard.

Again... thank you for your time! Your knowledge and expertise if greatly appreciated!

IMG_1086.jpgSLOT 1.jpgSLOT 2.jpgSLOT 3.jpgSLOT 4.jpgSLOT 5.jpg

[modem7]

Lots of IBM 5150 information at minuszerodegrees.net

I had plugged the 5151 into the wrong monitor port - unfortunately, when plugged into the other port... I got nothing... not even a green box.

Careful. The IBM 5151 can be damaged if it is plugged into the wrong type of video card.

Separately... I have pulled all the cards and photographed them and the motherboard.

Photo #1: The 16KB-64KB type of 5150 motherboard. More information at [here].

Photo #2: Quadram Quadcolor I, a CGA compatible video card. The operation manual is at [here].

Photo #3: IBM Monochrome Display and Printer Adapter, usually referred to as simply 'MDA'. Some information at [here]. You have the early version of the MDA card, which is discussed at [here].

Photo #4: A multi-function card made by Tecmar. Contains some RAM (4 rows of chips at far left) to complement the motherboard RAM, a real-time clock, a parallel port, and a serial port.

Photo #5: ????

Photo #6: IBM 5.25" Diskette Drive Adapter. Some information at [here]. You have the early version of the card, which is discussed at [here].

[srm]

Photo #5 is a PGS Scan Doubler II, used to convert CGA to VGA, read more here

[phonophan]

Thanks, again, for the quick and kind response!

Photo #5: ????

With regard to the card in question, in my original post... there's a "shortie" cable going from the Quadram Quadcolor I to the bottom port of that card. When I plugged in the PGS SR-12 monitor to the top port of that card, the monitor worked.

[romanon]

Thank you for the quick and kind responses!

I had plugged the 5151 into the wrong monitor port - unfortunately, when plugged into the other port... I got nothing... not even a green box.

Separately... I have pulled all the cards and photographed them and the motherboard.

Again... thank you for your time! Your knowledge and expertise if greatly appreciated!

IMG_1086.jpgSLOT 1.jpgSLOT 2.jpgSLOT 3.jpgSLOT 4.jpgSLOT 5.jpg

Man, as I can see, this should be very early IBM PC, please check your serial number on the back of case. I suppose that your SN is lower than 0(1)20000.

[gepooljr]

This is an amazing find. Congrats and welcome to the forum!

[SomeGuy]

If I am seeing the motherboard dip switches correctly, it is set to start up with CGA. That means you will need to connect some other monitor to the composite/RGB output, or change the DIP switch setting for now.

Many games can't do anything with an MDA (text only) board, requiring at least CGA instead. This sort of early dual video card setup was not too uncommon as early CGA monitors were often not very suitable for reading text.

That is a very strange passthrough video card. If I am reading that right, it says "Scan Doubler II Rev B". Not much info out there about it. It sounds like it would be used to interface with later higher resolution (VGA?) monitors. I don't know if that would require a software driver. At any rate, if you don't have the monitor it was to be used with, you probably don't need that card.