IBM 5170 help

Weezer · 29 Jun 2020, 19:26

I recently picked one of these up off Craigslist. I tried to post to VCF but my post was blocked I guess because it disappeared into the void.

I don't know anything about vintage computing so I was just hoping to get some quick advice about what I should check / clean / replace before I power the PC on. I don't have a monitor for it so I was also hoping that I could adapt it to VGA easily, and I don't know the best way of doing that. The computer came with the 3D CAD adapter card which only has a serial out.

Thanks for any help guys

JP! · 29 Jun 2020, 19:41

Some pictures would probably help. These usually have an IBM Color/Graphics Display Adapter (CGA) card but maybe yours doesn't? Also VCFED is a slower paced forum. It takes a while for posts to show up and I think are approved by a moderator, at least for new members.
http://nerdlypleasures.blogspot.com/201 ... -card.html

And adapting CGA:

JP! · 29 Jun 2020, 19:45

Weezer · 29 Jun 2020, 20:25

Nice, thanks for the replies JP! I'll definitely look into that when I can (I can't watch videos atm).

Are there any parts I should likely replace or clean before I power the computer on? I had another old PC that I accidentally blew the motherboard up on when I tried to turn it on because the PSU had bad caps. Is there a way to do a test or are there other known issues that these PC run into etc that you or anyone knows of?

JP! · 29 Jun 2020, 21:01

Well you can definitely run into power supply issues and you might know until you try to power on. A power supply can at least be changed with a more modern replacement or caps can be replaced. I'm afraid I'm not of much use when it comes to testing this power supply. I believe it needs some kind of load before you can test the voltages so there is a trick to that. You could try and visually inspect components. As far as testing caps, resistors, etc you would have to remove them to actually test them. Rather than replacing old caps some hobbyists will even try and first recondition / reform the electrolytic capacitors before putting a machine back to service. I you decide to bite the bullet and try and power up I would at a minimum visually inspect components if possible and also remove unnecessary add-on cards or other peripherals like drives until you know you have a working machine.

Some known issues:
http://minuszerodegrees.net/5170/proble ... issues.htm

OleVoip · 30 Jun 2020, 14:18

I would do the following with a device that has not been switched on for decades: https://antiqueradio.org/dimbulb.htm

JP! · 30 Jun 2020, 14:27

Oh, and another thing, I'd recommend powering on old computers outside should the magic white smoke try and escape. I powered on a computer once that I soon found out was notorious for it's tantalum caps exploding when powered on after many years of non-use.

inmbolmie · 30 Jun 2020, 15:12

I'd suggest if you have a CGA card and don't need to keep it original to directly get any cheap 16 bit ISA VGA card off ebay. CGA is underpowered for a 5170 and the VGA card will be even cheaper than an adapter.

But if you have an IBM CGA you will also have a single RCA connector in that card that is a composite NTSC video output, that you can plug to any TV set that supports NTSC. That way you can at least test the unit without additional hardware.

If that's not he case, it could be a MDA card if it has an additional DB25 connector, or an EGA card if it has dip switches and two RCA connectors. Those cannot be plugged in directly to a TV unfortunately and will require conversion or the appropriate monitor.

JP! · 30 Jun 2020, 15:22

inmbolmie wrote: 30 Jun 2020, 15:12 I'd suggest if you have a CGA card and don't need to keep it original to directly get any cheap 16 bit ISA VGA card off ebay. CGA is underpowered for a 5170 and the VGA card will be even cheaper than an adapter.

But if you have an IBM CGA you will also have a single RCA connector in that card that is a composite NTSC video output, that you can plug to any TV set that supports NTSC. That way you can at least test the unit without additional hardware.

If that's not he case, it could be a MDA card if it has an additional DB25 connector, or an EGA card if it has dip switches and two RCA connectors. Those cannot be plugged in directly to a TV unfortunately and will require conversion or the appropriate monitor.

Those are some great ideas.