Repair-It

Is it this kind? https://youtu.be/pk9lbLOksE8?si=ObI7qrTyf-vlP1iY&t=579

EIA standard tantalum chip capacitor? Needs more research. Hopefully these are the kind that don't leak.

Internet says dry tantalum caps don't leak as long as the "outer coating" is intact. It also seems like even if they are the wet kind, the electrolyte is actually retained inside unlike the cheap aluminum kind that I am replacing. I may try to check a few in circuit and not worry about it much further. Phew.

Replaced the 3 aluminum electrolytic caps as planned. Seems to work fine and has had no further errors. It's been working pretty hard, too, as I installed Windows 95 and some other stuff.

More pics. Ended up installing IE 5 but it only supports 40 bit encryption so still not what I need. It does hit Google though.

Retrozilla had WAY too high of hardware requirements.

I also went down a rabbit hole because the filesystem is running MS-DOS compatibility mode. But I think the reason is because the ESDI system (and the MCA port it uses) is 16-bit. So the system is just too old for 32-bit hard drive stuff. Oh well.

Took a closer look at my NIC. Turns out I have rev E of the old version of the PCB. Perhaps there is something wrong with my AUI adapter. Or maybe I should replace the three electrolytic caps...

https://www.ardent-tool.com/NIC/3c523.html

Then I found this:
https://www.ardent-tool.com/NIC/Ethernet_Bench.html

In theory the 3C523 is a decent card....

So I splurged and ordered TWO.

Card 1.
https://www.ebay.com/itm/232841819187

Olicom 2335 which is a 10/100 card though the link above says it is cheesy. I guess cheesy means ISA hardware barely adapted to MCA (therefore not taking advantage of anything). Also tiny buffers. I'll give it a whirl as it is reportedly the only MCA card capable of 100 Mbit. They tested it to about 24 MBit which is far short of 100 but I'll note is higher than 10.
https://www.ardent-tool.com/NIC/Olicom_OC2335.html

Card 2.
https://www.ebay.com/itm/205303434553?_ ... R9Sd7P6jZQ

IBM Lan Adapter/A
A 32 bit card that supposedly works in a 16 bit slot and that's the only free slot I have so it better. Like the Olicom it has on-board RJ45.

This card seems like quality hardware and also had some fast transfer rates with low CPU utilization. That's something. About 8.6 Mbit which is similar to my 3C523 but using almost half the CPU on a 486.

https://www.ardent-tool.com/NIC/LAN_A.html

We'll see how the machine and Win 95 likes these when I receive them. Just want a functional NIC (receive performance has always been unexplainably slow, even 21 years ago according to some archived e-mails I found).

So for the network I can just sell whatever I don't want to keep (including my old 3C523).

But I also ordered a "new" sound card.

https://texelec.com/product/resound-new-wave-mca/

This is on backorder so hopefully it is fulfilled at some point. Ordered it on 2/11 I think. I guess I may end up getting a NIC or two before the sound card. Also, these new cards will have to share the 16-bit slot as the two 32-bit slots are taken up by important stuff: XGA/2 card and RAM card.

Needs moar tower with more 32 bit slots. Then I could get a 32 bit SCSI card and have some performance for my file system. The Model 80 is the tower version and has many slots.

Olicom card I think the card works (it had link lights that lit up) but I could not make the Windows 95 driver work to save my life. I think it works in literally every other OS. Sigh. So this one is probably going back to eBay (to sell).

If I have the patience, I might try the 16 bit Win 3.x driver and see if I can get it working that way. I think I'm selling it either way but in the interest of fill disclosure I can report what I know about the card's function in my eBay ad. And frankly if the 16 bit driver worked that is a better story than "it didn't work at all for me."

Then my reference disk that I've been adding to just....blew up. Made a brand new one with one of my new 3M disks (the old one was on one of my old CompuServe disks). Making the stock disk is easy as it's an executable self extractor disk image maker. But then I have to one by one add the option disk stuff to it for the cards I have otherwise it doesn't know what to do with any of the cards and can't auto configure itself.

Next I tried the IBM LAN Adapter/A. It turns out I didn't understand the ad - this card was new old stock. Crazy. Even crazier it seems to have been made in 2003. That is really late production. The card has been around since the early 90s (in an older board revision) so that is nuts. Looks brand new, and smelled brand new. In original packaging. That's cool.

This is a 32 bit card but it has a notch on the bus connector to fit into a 16 bit slot and it will work in 16-bit mode. I did plan for this and sure enough it slid right in and the dangling extra 32-bit section didn't interfere with anything on the motherboard.

Booted up, did the option disk thing, configured the system (as you can see above) and it was good.

Booted Win95 expecting plug and play. It turns out I don't think MCA supports real plug and play. You have to run the add hardware wizard but with the 3Com card, it would just find the card and work. Not the case with the IBM card. I thought it would just have a driver. So I went looking for drivers and wouldn't you know - there is no Win 9x driver for this damn card. WTF!! There is a driver for every other OS, like NT, OS/2, DOS, Linux. My only option was to run the 16 bit real mode driver for Win 3.x (Win 95 did support this but it chokes performance). That part installed just fine, though it took a while (it loves to request random Win 95 install disks every time I touch network config).

Anyway, the card was working fine now. I installed TCP/IP and did the usual and I was able to ping it. I still couldn't access my Dell laptop via network neighborhood (same with the old 3Com card) which must be a 95 to XP thing not a NIC issue BUT I did test bandwidth by accessing the Model 70 via my Dell. The results? Seemed to transfer files at a reasonable pace now, and mostly saturate the hard drive. MUCH BETTER! Now I'm not getting optimal like DMA/bus mastering/whatever performance from the card with the real mode driver but the whole point was to improve the LAN file transfers and that part was a success!!

In fact I backed up the entire hard drive (minus Windows directory) and that didn't take much more than 10 minutes. We'll call this a win.

So the Olicom definitely is going back to the eBay market (I won't even bother attempting to return to seller based on the policy in the ad). It may be 10/100 but it's basically an ISA card lazily adapted to an MCA form factor with zero extra functions to improve performance. The IBM card is cool so I'm glad it worked in the end even if suboptimally.

Tried the Olicom again and couldn't find a different driver to install so I did the same thing again and got the same results. So it's going on eBay.

Removed everything so the slot is empty, preparing for my sound card delivery on Wednesday!

In the meantime I decided to give the XGA drivers another whirl. Actually I did two things. I also found a Hitachi monitor driver file which had my 15" monitor in it. Then for the updated XGA208 driver, I somehow had the idea to update the driver within device manager rather than as a new hardware device. I just opened it there and pressed change driver or whatever and selected the XGA208 drivers. To my astonishment, this worked! I guess this is all I was supposed to do originally. I think the update only changes like two key files so if you try to install the hardware from scratch, it is missing a ton of stuff so it doesn't work. But if you change driver it keeps everything important and only changes certain files? Either way it worked.

I do have 800x600 @ 16-bit now (original driver only did 16-bit @ 640x480) and I was able to do 1160x870 @ what looks like 75 Hz (or something over 60) in 256 colors. So much room for activities.

So I guess there are other Olicom drivers that I didn't see on the Ardent site. Meh. The IBM card is fine.

Auction is live.
https://www.ebay.com/itm/156753437248?m ... media=COPY