This one looks like a closer match, a Soyo SY-030G: http://www.win3x.org/uh19/motherboard/show/4717

EDIT: Found a manual and a BIOS. They're on uh19.

It looks similar to this ABit https://www.theretroweb.com/motherboards/86

thank you so much , I will check now.... I
L.E.
ok thank you so much , I can confirm that http://www.win3x.org/uh19/motherboard/show/4717 is correct ,
*however my board dose have some missing jumpers , but its great , thanks , starting the Jumper setup-now

Ok,
so, after a long and epic journey , I finally managed to boot /post the 80486 . (check out first date since project begone).

This setup is close to my first pc I got in 2000 april.
Motherboard is the original , and I had it since 2001 in closet. ( I lost hope of ever booting system up again , but chance gave me a nother"GO" - !" Never give up in trying to fix your vintage stuff! ")

- Yesterday I started again tinkering with the machine , disassembling it and trying to fix her.
- Disordered old bat , cleaned , re-made trace with solder (was only a bit broken off under battery from corrosion)
- Soldering 2 wires and a 3,6V nicad battery at other end.
- And still ! "NO-GO"

then searched for manual again (posted below) , tried 5 variation of jumper settings , keep getting blank screen no POST (boot) , no beeps
- Eventually I figured out my beloved machine has a special cpu mounted, 80486 DX2 i66 with write-back and 5V ( learned AMD , cyrix and other intel have 3.4v-3.45v-3.6v )
-So eventually after trying many many failed jumper settings , I figured out manual says to use Intel P24D CPU (w/ Internal write-back cache) *66 (mhz) 5V - so I had to ad a few additional jumpers from lot for it to boot-up/ P.O.S.T. / start .
- Was a journey , Always remember to identify correctly the CPU and correct voltage for correct CPU , if you don't it won't post and you may think you have a broken MB.

Wanted you all to learn from my mistakes and 3x check manual and webpages. + Jumper settings (it may fail if it's misaligned).
- Info on this regard is scares so decided to post my adventure

Now I am happy to report that I have a Working Intel ¬ P24D CPU - 80486 DX2 i66 with write-back and 5V with
MB (motherboard) SOYO 85C496 + 85C497
48 ram (2x8 mb double side + 2x16mb EDO single side)
S3 PCI graphics (was tested before initial install in system)
WD 4.3 gb hdd (that clicks randomly not sure if its hdd or power-unit to blame , may not have a linear amperage/voltage). with overlay to be identified (still working on this).
MS-DOS Command.com loads .

More of this setup and adventure to come. (not worth opening different topic) so I will continue here. (want to install dvd-rw , 5.25" floppy , 1.44mb floppy, hdd 5.25" internal rack all on old white colour).

SIT.REP. :
Here is next what I did , (on my 486) ,Mount 2x8mb +2x16mb edo and wrong bios settings on a incorrect hdd controller.

Spoiler alert it turned out to be bad ram + wrong bios cache settings (so turned all off to finish installing win95) :

Here is what I did ,
Load all files on hdd externally , mount hdd ,
get angry because it was not booting setup,
then , remount hdd externally to laptop over usb, use hirensboot to load dos , copy all on hdd, try loading win95 setup , loaded but did not start , gave me a error ,

then use second laptop to make a bootable usb thumb drive so I can load the EZ-Drive 906 *yes hdd WD43 * 4.3gb was already partitioned with overlay.
booted of that and then the win95 setup started
(-from the external drive mounted to newer laptop) , gone 50% setup , than it hung , so I rebooted ,then I pulled the drive from laptop as it would not go further.
Mounted in 486 , tried different combinations till I figured out how to setup bios hdd in user mode, setting up the drive by copying settings from EZ into bios - mine was int 13h - 80h cyl524/h255/sect63- capacity 4302MB &the rest off.
Still no go , it hung .2x IDE cables l8ter ,and additional ide 100ata controller l8ter that would not detect drive, *then I started win95 with shift key and discovered that it would give me unreliable memory . (mind you I had no floppy controller or floppy in 486).
So I decided to pull all ram out , and test one by one turned out EDO would not even boot (so out of 4 modules) ended up scrapping the 2 edo 16m , and out of 2x8mb double sided ram ended up using 1x8mb simm 72pin.
Still didn't go. So finally searched web and a 20 year old forum, & at the bottom someone wrote to try disabling all caches from bios.
So after disabling everything it finished installing win95 on 8mb of ram. It turned out that from main Award 4.5 menu the Second cpu cache - External cache ! was the culprit .

Turned on nothing worked turned off windows would load. (I don't know rest , because I keep turning everything on and loading windows , all worked ok , at least seems so ). I will have to check memory for additional errors.

Moral of story LOAD DEFAULT ON BIOS then turn everything off. re-check . if installed (win95), one by one re-turn on caches and stuff.

As this chipset tends to have problems with EDO DRAM, please check the chipset revision first: SiS 496/497 revisions
You may try FPM DRAM too, that should have less conflict potential.

upgraded to 16mb of ram .... recently (second module seems to boot fine with ) ... PC seems stable. (still unable to locate my isa floppy+com controller) so no mouse and floppy yet.

Win95 on a DX-2 ??? not the correct match.

nuno14272 wrote on 2023-04-20, 10:14:

Win95 on a DX-2 ??? not the correct match.

Elaborate? I also have a 4.3 gb drive and put all the utility'es from hiren's boot , VC and NC....

Just that a DX2 is weak for windows95... so very slughish...

when using what are your feedback on windows speed ?

Depends.
If you have a processor in DX2 mode you can clock FSB to 60 MHz to get 120 MHz, you even can play MP3.
(A candidate is Am486DX4-SV8B 120 in x2 mode)
But the mainboard is heavily overclocked then.

You'd better use a DX4 or 5x86 in that board.
But you have 256 kB of L2 cache in a single bank. For fastest timinigs (2-1-1-1), I recommend to not go over 33 MHz FSB.

It's good enough , will test with winspeed app.... was first pc, I set it up for as it was most days in pre-teen-period. (486, same mb ,16 m of ram , and a 10x larger drive). I use to browse internet with this config back in the day during dail-up world.(at the turn of the milenium)
It has high fsb , its a 486 Sport, managed to turn on almost everything in bios. I will edit the time-ing's , winamp runs fine. (no audio yet and no floppy controller).

I need it for nostalgia + dos if I ever want to load something outside win. (I don't want 3.1 hassle on this 486, if I can run win95 ,prefer to stick with this).

BTW I checked I don't have anything that fit's only K5-s and K6-s ,pentiums and so on.