AT&T Catalyst PB5500C ? Could be a Mitac PB5500c motherboard....

Looks a lot like this.

http://www.uncreativelabs.de/th99/m/S-T/32638.htm

It looks similar but it doesn't match. The bios is where the 3rd VLB slot traces should be, there's a 8bit ISA slot and none of the jumpers are matching.
Also it's still on Shuttle's website and they clearly say it's a socket 5 board https://www.shuttle.eu/_archive/older/de/543.htm

On a whole other note - is that battery going to leak?

H3nrik V! wrote on 2020-08-28, 08:34:

On a whole other note - is that battery going to leak?

I was planning to remove it as soon as I get the board, but looking more closely at the pictures it seems to be a Lithium cell and not one of the usual NiCAD barrel batteries. I don't think Lithium batteries are prone to leaking like other types, but if there is an external battery header on the board, I'll probably remove it anyway. Either way, I'm sure the battery on there is long dead.

Can You help me identify this motherboard and find manual?
It came with VLB controller and P60 cpu

Shuttle HOT-523

Informations here http://www.win3x.org/uh19/motherboard/show/4444 and there too http://www.shuttle.eu/_archive/older/de/523.htm

Thank You

the board in the first post looks a lot like my QDI Legend socket 4 mainboard. Same chipset, same board layout, but my board has all 3 VLB slots soldered on. Can't remember the model and I don't have it on location, but I'll check when I get back home.

@lukasp12: can you make a bios dump and post that here? We then can add it to the page for your board in Ultimate Retro:
https://www.ultimateretro.net/en/motherboards/4444

The first board is indeed MiTAC, the numbering scheme matches and there's is a 411-xxxx-<whatever> which is typical for MiTAC. This may be an OEM version seeing a VLB slot is not mounted.

evasive wrote on 2021-01-31, 19:48:

@lukasp12: can you make a bios dump and post that here? We then can add it to the page for your board in UH19:
http://www.win3x.org/uh19/motherboard/show/4444

Hi This is my BIOS
08/24/94-OPTI-596/546/82-2A5UIH21-00
The other BIOS on that page doesn't work for me, is is twice bigger and even with other rom chip it doesn't post.

I have problem, I can't boot from HDD. Computer wasn't in use since I post here in September. Now it recognize HDD in BIOS, but not boot.
It boot from FDD and then I can use HDD, so HDD works, but not boot.
It uses VLB controller. BIOS is set to defaults.
Any suggestions? I will try ISA controller from my 386 letter.

"can use HDD" you mean you can read the disk, files and etc.

What operating system is on the HDD? DOS, Windows, Linux?

evasive wrote on 2021-02-06, 20:09:

"can use HDD" you mean you can read the disk, files and etc.

What operating system is on the HDD? DOS, Windows, Linux?

Yes, after boot from FDD I can use HDD, run programs/games.
On disk is DOS 6.22 and Win95, but I have swapped it with disk from working 486 with DOS 6.22
I have changed IDE cable and VLB port.

Try booting from a DOS/Windows 95 boot disk (make sure the boot disk you use matches the OS on the drive you want to boot from) and run FDISK /MBR (It won't say anything in response.)
If that still doesn't work, reboot from the boot disk and try SYS C:
If even that doesn't work, you'll have to re-partition the disk using FDISK on the system you want to use it in (meaning, don't put that drive back on the 486 to do it), and format it afterward. (Afterward, you can copy all the files to it from a different computer.)
Sometimes the BIOS doesn't like the disk's boot sector if the disk was prepared/used in a different machine prior. I've seen this happen many, many times, and usually I am able to work around it via FDISK /MBR or SYS C:.

SYS C: helped, thank You

@Eep386, thank you.

I had a busy day yesterday so didn't visit the forum.