VOGONS


First post, by Lylat1an

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I'm looking for a motherboard that can run DOS and Windows 9x games in my favorite retro case.

I was using a Super Socket 7 Asus P5-99B, but it now has bad capacitors: However, its RAM and CPU positions come right up against the IBM's drive cage without interfering with it.

https://theretroweb.com/motherboards/s/asus-p5-99b

Might anybody know a modern replacement board I can use without having to use lower specs?

(Please don't advise the Corvalent Gator AT, I've looked but can't find one)

Reply 1 of 9, by Horun

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Might be easier fixing the bad caps or find same board. Sorry have no answer.
Long ago (mid 1990's) used some old IBM cases and built them into 486's for my friends to play Command and Conquer via modem, also played Doom, Heretic and Hexen and we had a great time !
Yes it was a chore to find a 486 board that cleared the internals....

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 2 of 9, by Dan386DX

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The switch over to ATX and mATX began in 1997, some of the last boards to use Baby AT were Super Socket 7, Slot 1 and Socket 370.

You could pick up a Socket 370 Baby AT board and a Pentium III 500, on eBay or a Celeron Mendocino. There were some Slot 1 Pentium IIIs as well.

Horun does have a point though, getting the caps fixed might be cheaper.

90s PC: IBM 6x86 MX 233MHz. TNT2 M64. 256MB RAM, 2GB CompactFlash.
Boring modern PC: i7-12700, RX 7800XT. 32GB/1TB.
Fixer upper project: NEC Powermate 486SX/25. 16MB/400MB.

Reply 3 of 9, by darry

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You will likely find a multitude of newly made industrial ATX boards meant for older CPUs and sporting ISA and/or legacy PCI slots, but AT format ones appear less likely.

Maybe you could consider using an ATX board and adapting it to fit in your preferred AT case non destructively. I believe this has been done before.

Reply 4 of 9, by dionb

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New? In 2024? Not very likely except at extortionate prices.

Instead, take a look at a PICMG 1.0 backplane, many will fit in the case. Then get a PICMG 1.0 SBC with desired CPU/chipset on it. Prices aimed at B2B market can be horrendous, but I frequently spot them at more reasonable rates. I recently got my hands on a Pentium M SBC for a few tens of EUR, and yesterday an eBay auction for a Pentium Pro one ended with no bids for GBP 100, tested and including CPU, heatsink and RAM. Was sorely tempted until I saw expected shipping & duty rates.

Reply 5 of 9, by Disruptor

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I use a K6-2+ 533 @ 400 MHz in a board that does not have support for 100 MHz FSB.
Before I had an Intel Batman(?) board where 3 of the 4 SIMM connectors where with a flat angle.

Reply 6 of 9, by Lylat1an

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dionb wrote on 2024-04-15, 09:59:

New? In 2024? Not very likely except at extortionate prices.

Instead, take a look at a PICMG 1.0 backplane, many will fit in the case. Then get a PICMG 1.0 SBC with desired CPU/chipset on it.

I've actually looked into those before, and the SBCs appear (at a glance) to be a bit too tall for a 5160 case.

Reply 7 of 9, by Lylat1an

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Horun wrote on 2024-04-15, 04:37:

Might be easier fixing the bad caps

I took the board to a friend who does that service, he said he couldn't source any of the proper capacitance.

Reply 8 of 9, by Lylat1an

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Lylat1an wrote on 2024-04-15, 15:03:
Horun wrote on 2024-04-15, 04:37:

Might be easier fixing the bad caps

I took the board to a friend who does that service, he said he couldn't source any of the proper capacitance.

Now that I'm looking for myself, I'm seeing several options for them online.

Is Amazon a good source?

There are only three 6.3v 1800uf caps that the guy couldn't do while he was working on it, and they look similar to the ones in this listing:
https://www.amazon.com/Cermant-Capacitor-0-31 … s/dp/B0CGCRK4K4

Reply 9 of 9, by mkarcher

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Lylat1an wrote on 2024-04-16, 04:38:
Lylat1an wrote on 2024-04-15, 15:03:

I took the board to a friend who does that service, he said he couldn't source any of the proper capacitance.

Now that I'm looking for myself, I'm seeing several options for them online.

Is Amazon a good source?

I strongly recommend buying low-ESR caps from an established reputable brand like Panasonic, Nichicon, Universal ChemiCon or Nippon ChemiCon. I don't recall I ever heard of the brand shown in the picture. Furthermore, products on Amazon Marketplace have higher chance of being cheap crap with a fake label than buying at a reputable electronics retailer like Digikey, Mouser or Farnell. Possibly you also have local options.

Lylat1an wrote on 2024-04-16, 04:38:

There are only three 6.3v 1800uf caps that the guy couldn't do while he was working on it,

Don't get too hung up on the 1800uF capacitance (which is quite uncommon indeed), and just go for 6.3V 2200uF or 10V 2200uF. Make sure the replacement cap has the correct lead spacing ("pitch").