Could you post a pic of the board?

Check here:
http://www.win3x.org/uh19/motherboard/result/?name=um8810

It has Dallas real time clock, go to youtbe and look up for "dallas (or rtc or the model written on the rtc) battery hack".
The battery is embedded in this RTC that has the clock inside. You need to replace that battery.
If you have some basic soldering skills it's easy to do. Or you can buy anew one on ebay/aliexpress.

It's a common issue of all the boards that come with a RTC, one day or the other they go flat and you have to either replace the whole thing or just do the battery hack.

Yes, it's Dallas.

Ok, you have to remove the RTC.
You either unsolder it or do the hack, there's no way around unscrewing and soldering.

Watch some videos on how to. Don't rush things.

For archive purposes:
Can you post a pic of the boot screen?
Save the bios and upload it here?
When you are going to get the board out, could you take a good pic of it?

Have fun!

Edit: if it's soldered it'd be best to resolder a socket to avoid having to desolder again in the future. A lot of unnecessary work avoided.

I'll try soldering new battery.

Here's some pictures, made few days ago, dissasembled everything to pieces, removed dust and assembled back again. I'm really new to this old PC stuff, first I'll try to fix battery problem, next there's no OS installed (or HDD dead) so fix that, and last, fix COM/LPT adresses.

Is there any tutorial how to save and upload BIOS file? I have spare floppys laying around, but don't have another PC with diskette drive.

Can you please shoot a nice photo of your motherboard with good lighting and angle so we can add it to UH19 ?

A bios dump would be appreciated as well 😁 (I can help with that)

Well, PC has been assembled and I have no intention to take it to pieces again 😀

Is the RTC soldered or socketed?
Can't really tell from the pics.

I just took it out, not soldered.

Like in this video https://www.youtube.com/watch?v=IbiczYoVncQ

Fanax wrote on 2020-12-17, 17:24:

Well, PC has been assembled and I have no intention to take it to pieces again 😀

Oh, that's too bad 🙁

Well anyways, I'm just saying, it'd be really helpful ^^

Also I noticed that your board has the "ECS" VRM !
Could you at least take this one off your board to take high res pictures of it ? I know other boards use that kind of thing, and they're unobtainium in the wild. Having high res pics of it would help a lot to replicate it !!

For the bios, put the content of that archive on a disk and run "romsavat.exe".

It will backup your bios to a file.

Now, to get that floppy disk issue sorted out, do you have any computer from the windows XP/vista era ? These should have a floppy disk connector in them. If not, you can either :
get a USB floppy drive or, get a Gotek floppy disk emulator for your computer. You'll need disks (or emulated disks) to install your OS anyways.

If you still have original DOS/windows 95 disks meaning you can install an OS on your computer without messing with more modern computers, you can also install a network card in your computer and then run a ftp server on your retro PC and accces files through the network, or a PCI usb expansion card, or use a nullmodem cable, replace the original HDD by a CF or SD card meaning you can just take that flash card and put it in your PC ... There are many solutions and all are good solutions depending on what you want and the context ^^

Which one is ECS VRM? Could you point it out on board? I might take out board in near future, then I'll make proper pictures.
I'll try to source out old computer with floppy. Where to download Windows 95 installation files?
I have few PCI 100mbit network cards, but they are much newer than this machine, doubt it will work.
My main goal with this machine is to bring it back to life, with no errors whatsoever, Windows 95 and replay Doom 2 and Heretic 😀

The vrm is the separate circuit board hanging off the board right next to the CPU socket

For the network cards you might be surprised 😀

Some 1Gbps cards from realtek from the 2000's still have DOS drivers.

I'll add proper photos, when I'm done saving this 😀

So, I manage to solder battery. It works. Now, second wave of problems 😁

1. Front panel shows Normal-40 and Turbo-180. This must be wrong... right? How to fix it?

2. BIOS shows no problems only when I select Diskette Drive A 360KB 5 1/4, but it must be wrong setting...?

3. Windows 98 only boots in safemode, when I try starting in normal mode, it just freezes, even mouse freeze. Also, it takes like 3min to boot.

Fanax wrote on 2020-12-20, 21:28:

I'll add proper photos, when I'm done saving this :) […]
Show full quote

I'll add proper photos, when I'm done saving this 😀

So, I manage to solder battery. It works. Now, second wave of problems 😁

1. Front panel shows Normal-40 and Turbo-180. This must be wrong... right? How to fix it?

2. BIOS shows no problems only when I select Diskette Drive A 360KB 5 1/4, but it must be wrong setting...?

3. Windows 98 only boots in safemode, when I try starting in normal mode, it just freezes, even mouse freeze. Also, it takes like 3min to boot.

1. Those aren't set by the computer, those are set by the led panel itself. It only recognizes ON= display 180 and OFF= display 40.
You have to set it manually and that's on you to figure out how as settings vary from model to model.

2. If you have two connectors on the floppy cable try switching it to other one and see which one works 1.44M 3.5.
You could update the bios.

3. Why it freezes can't be determined just like this, there could be a hundred reasons why. Maybe wrong drivers.
3 minutes with a mechanical HD could be right. Not SSD drive there, and speeds vary greatly from HD model to another.

On both of your photos, the LED of the floppy disk drive is turned on ... Does it turn on right when the computer is on ? If so, reverse the floppy cable's orientation, because that's what happening when the cable is inserted in reverse.

As said, the turbo display is independent of the motherboard and has to be configured manually.

Also don't expect 98 to run very smoothly on this. It's a 486, not a pentium 2 ^^
(I don't think it should take 3 minutes to boot though). You may improve dramatically the performance using "98lite".

Tried both sides floppy cable, still not working. Tried different Floppy drive - not working. Or it not supossed to work under Windows safemode.

Found diagram for front panel http://minuszerodegrees.net/led_speed_display … 568%20S305H.jpg but still can't figure out jumpers...

The way you configure these is :
Each jumper can configure a segment of the display.
You can configure each segment to be :
- On for turbo, off for de-turbo
- Off for turbo, on for de-turbo
- On for all modes
- Off for all modes.

As for the floppy cable, make sure it's at least properly oriented. The LED shouldn't stay ON all the time.

Also you need a floppy cable with a small twist in it. Once you see it, you have to connect the floppy drive after that twist.

First connector from left to the board and fourth connector to diskette drive..? Also, I think CD-Rom is not working, or isn't connected properly.

Yes.

What makes you think the CDROM is bad ? Do you use pressed discs or burned discs ?

On every flat cable, the red border indicates PIN 1.
On the motherboard you have to connect the cable with red border on pin1, in the pic it's the left side connector.

You have to select "slave" on the cd rom. Sharing the same cable the bios needs to know which one is master and slave (device n.1 and n.2...).

You don't have much experience with this old stuff, don't you? 😀