Short answer - that should be fine.

I have recap experience, especially with vintage audio.

Yes, the 1800uF is more capacitance, but these are most likely being utilized for ripple filtering. I doubt the extra 20% is going to be significant enough for the initial in-rush current to upset the power supply.

Was the board function recently, prior to re-cap? Old electrolytic caps tend to increase in capacitance as they age - the original caps, if they didn't fail completely, would probably measure 1600~1700uF.

Nichicon was my personal favorite thru-hole electrolytic, but as those have become unavailable in many sizes, I have substituted Panasonic regularly. IMHO, no need to second-guess the brand choice.

Hi Fazeshift,

thank you for your expertise! I'm glad to read that 😀
I can't say the board didn't work prior to recapping, last time I used it it worked fine. At some point I noticed they were bulged, so I decided to get them off the board. It's some sort of a project for me with this little mobo, as I want to populate the Through-holes for an ISA slot which is not placed by default on this board. So what I'm doing now is put an ISA slot on it which I salvaged from another board of mine and see if that will work with an ISA soundcard (cause we all know it's not true retro if it ain't got no ISA slot). And while I'm at it I also did the recap, although it might not have been necessary really.

Just a FWIW, one my my favorite series for recapping older gear is Rubycon ZLH. Some will argue this to death (like ford vs chevy; republican vs democrat)....but I've been recapping since 2002 and picked up ZLH when Rubycon discontinued MBZ and MCZ; and have never had an issue.

It was definitely the right move to get any caps off the board if they were visibly bulging and/or leaking electrolyte. Early slot 1 (and late super socket 7) was peak capacitor plague.

I would suggest testing after the re-cap, prior to doing the ISA slot modification. If you run into any issues, it will make diagnosis a lot easier.

DOS and ISA sound cards are my favorite retro era, so I'm with you on the ISA slot.

Out of curiosity, which on-board audio chip does this board have? I recently got a slot 1 board out of storage, and was excited to find a Yamaha audio chip - a YMF724 which is PCI but has legacy SB Pro support. I found a schematic for the motherboard, and unfortunately they never bothered to route the necessary pins for legacy support (IRQ, etc) to the South bridge.

Twisted Six wrote on 2026-02-24, 18:47:

Just a FWIW, one my my favorite series for recapping older gear is Rubycon ZLH. Some will argue this to death (like ford vs chevy; republican vs democrat)....but I've been recapping since 2002 and picked up ZLH when Rubycon discontinued MBZ and MCZ; and have never had an issue.

Agreed - cap brands are really a personal preference. I have also used Rubycon without issue, and would recommend.

The most important thing is to avoid low-quality or counterfeit caps. I would also rather have fresh stock of any decent cap brand from a reputable electronics supplier, than old stock of any brand that could have been sitting for a decade.

No matter what I buy I use a cheap ESR meter to check what I get is in spec before installing them. I think motherboard capacitors are +/- 20% of rating.

Twisted Six wrote on 2026-02-24, 18:47:

Just a FWIW, one my my favorite series for recapping older gear is Rubycon ZLH.

Thanks Twisted Six, I'll put those on my list for future projects!

Fazeshift wrote on 2026-02-24, 18:57:

I would suggest testing after the re-cap, prior to doing the ISA slot modification. If you run into any issues, it will make diagnosis a lot easier.

DOS and ISA sound cards are my favorite retro era, so I'm with you on the ISA slot.

Out of curiosity, which on-board audio chip does this board have?

I believe you are right, I'd better test that sepperately. Yeah, DOS and ISA are such good friends, PCI sound just isn't the real thing.
Onboard sound here is Creative ES1373 which I think is used on the cheapest Soundblaster AudioPCI 64 / 128 and the likes. It has DOS support but pretty crappy.

@Unknown_K
True, they do have quite big tolerance. I think I also have to get an ESR meter...

kickloch wrote on 2026-02-24, 19:27:

Onboard sound here is Creative ES1373 which I think is used on the cheapest Soundblaster AudioPCI 64 / 128 and the likes. It has DOS support but pretty crappy.

AKA "Ensoniq AudioPCI" before Creative acquired and started rebranding. I have a few in a box somewhere. It was admirable that DOS support was included for a PCI sound card/chip, but IIRC it required a TSR that didn't work with certain games/software. There really is no substitute for real ISA bus if you want the best DOS compatibility.

Yes, you remember correctly, I think it's called sbinit.com. And it requieres emm386 to load.

Hi folks!

I went all in with the board and have already placed the ISA slot. On the upside, the board is still alive. It's posting normally so the recap worked very well. Downside on the other hand is, the ISA slot just doesn't work. I don't know whether it is a BIOS limitation that renders the ISA bus unusable whatsoever, or are there still any SMDs missing on the board, did I make any soldering fault, I simply don't know. What I noticed is that HWiNFO shows only PCI and AGP as available bus systems, no ISA. That makes me wonder a little bit.

Anyway, it could have worked, but sadly, nope.

kickloch wrote on 2026-02-24, 21:57:

Yes, you remember correctly, I think it's called sbinit.com. And it requieres emm386 to load.

Oof, that must be why I left them in that box.

kickloch wrote on 2026-02-25, 17:53:

Hi folks!

I went all in with the board and have already placed the ISA slot. On the upside, the board is still alive. It's posting normally so the recap worked very well. Downside on the other hand is, the ISA slot just doesn't work. I don't know whether it is a BIOS limitation that renders the ISA bus unusable whatsoever, or are there still any SMDs missing on the board, did I make any soldering fault, I simply don't know. What I noticed is that HWiNFO shows only PCI and AGP as available bus systems, no ISA. That makes me wonder a little bit.

Anyway, it could have worked, but sadly, nope.

Is the board a Medion 9901? If so, is it the Intel 440ZX chipset or the Via version?

I once went down a bit of a rabbit hole related to Intel's PIIX4, which had a few different ISA-bridge modes. I'm thinking it is non-function because it is in the wrong mode, or perhaps there are some other unpopulated passive components required. I can't promise anything, but I could compare to the schematics I have for some similar boards.

Hi Fazeshift, thank you so much for your input!

Yes it is the Medion 9901. And it's got the 440ZX chipset. It sounds very interessting to me what you say about the bridge modes. My best guess would also be that there is some kind of "misconfiguration". As far as unpopulated passive components are concerned I don't believe that the problem lies here. There are very few spots with missing components, I'll show you in the picture below. But how would you alter the bridge modes? Is it a BIOS issue then?
Anyways it would be really cool if we could make it work. I appreciate your help, that's very nice 👍

Intel version, cool.

It turns out the Slot 1 boards (I have 4 of these) I mentioned are almost the same, architecturally - same Intel FW82371EB (PIIX4E, aka south bridge), Winbond W83977EF I/O chip, 3x PCI, and 1x ISA - mine is populated. I'm itching for some retro hardware hacking on mine anyway.

As for passives, I was going to ask you to check that all resistor networks (8-pins, labelled RNxx) are installed, but they almost certainly are since the ISA bus (starting at the PIIX4E) will be wired thru to the Winbond I/O chip.

kickloch wrote on 2026-02-25, 19:46:

But how would you alter the bridge modes? Is it a BIOS issue then?

Playing around with the chipset mode bits. It has been a while since I've done this - I still need to try a few things on mine first.

Yes, it is technically the BIOS setting the chipset modes on startup. If there was a BIOS version available for your board with ISA-populated, that would be the obvious answer, but none of the Medion 9901 boards seem to be optioned this way. I do see this might be an OEM version of the MSI MS-6190ZX board, but I would NOT advise the risk of flashing to that BIOS. I was thinking more along the lines of a DOS startup utility that can change the mode.

Hi Fazeshift,

yeah the MSI number of the board indeed is MS-6190(ZX), but I don't seem to find any original non OEM-variant of that one. Not even the Retroweb knows it. I believe it was built for OEM use only, a Medion exclusive in that case. I if had found a BIOS file for an original version I believe I'd already tried that, no risk no fun 😉 Although, the Medion BIOS seems to have the ISA pnp settings and all the stuff, making me believe that it could work in the end, as you see on the picture below.

Yes, the Resistor networks are all in place, I'll show you some more pics from both sides of the ISA slot.

I have used the programs from H. Oda back in the days, wpcredit and wpcrset which let you alter the chipset registers from within windows and on windows boot time respectively. Does it go in this direction what you mean?

Cheers!