And the socket up close

That would be for installing a 5volt 486 dx2 or 486 over drive CPUs. https://en.m.wikipedia.org/wiki/Socket_2

With that socket you can upgrade past the onboard 486sx cpu.

That's a great looking little system with the right parts it'll make a nice DOS/win 3.1 gaming system.

Yep could shove an p24t pentium overdrive in there or

And this is literally the only vintage CPU that I recommend overclocking.

Every SX I have ever owned overclocks to the limits of the motherboards stability, might need a heat sync but 40 or 50 MHz is possible depending on how stable your board is at high FSB

I put an sx16 into a Pcchips 912 and overclocked to 60mhz, Duke Nukem became playable .

Well worth a try for the cost of absolutely nothing

Also if the system allows for cache install some
That is by far the biggest speed booster .

Edit... Those brown slots are for 128k of cache, without a pinout and custom circuit board it will be hard to find

https://stason.org/TULARC/pc/motherboards/I/I … -25-D4-33D.html

Other option is to enjoy the system as is, lots of games run fine on a 486 just like yours and if you can reduce FSB/disable internal cache even ancient and speed sensitive games will run.

The reality is even with a 5x86-160 your system will be limited by video, lack of cache and a lack of local bus so best used for period appropriate games and older and the SX is probably fine.

Also a bit odd, the board was designed in 1991 but your build date is 1994

Seems to be listed on th99
http://dacccs.zapto.org/th99/m/I-L/32890.htm
and uh19
http://www.win3x.org/uh19/motherboard/show/3025

If you could take a nice photo of the board and dump the bios you could help out the people working on uh19 😀

Thank you everyone for your advice.
This is good news indeed. I have an old CPU+MB+RAM kit, that has suffered a catastrophic corrosion damage due to a leaked battery.
Please see the picture attached.
it is an AM486 DX2-66
I hope it is compatible and will attempt to add it to this little PC
Also add the rest of the ram.
Will post if successful

weedeewee wrote on 2021-04-09, 21:55:

Seems to be listed on th99 http://dacccs.zapto.org/th99/m/I-L/32890.htm and uh19 http://www.win3x.org/uh19/motherboard/show/3025 […]
Show full quote

Seems to be listed on th99
http://dacccs.zapto.org/th99/m/I-L/32890.htm
and uh19
http://www.win3x.org/uh19/motherboard/show/3025

If you could take a nice photo of the board and dump the bios you could help out the people working on uh19 😀

weedeewee , yes will do the next opportunity I have more free time from my day job.
I had removed the MB from the case when doing the DALLAS mod. It is quite easy.

Thank you all
Stichas

Alright It worked.

Good thing I had the original CPU fan. The BIOS detects it fine. But I did had to swap LAN and Sound blaster 16 cards in their slots.
Lets hope wont encounter any IRQ and DMA issues. Will update this thread when I sort out the software part.
Also - is there a good tool to dump the BIOS you could recommend ?

One more thing. Hope Google will index this part: !!! ICL ERGOPRO C4/33 to enter the BIOS settings you need to pres ALT+INS key on boot. Not only INS key !!!
Took me a while to figure out and no guides mention it.

Kind regards
Stichas

Excellent. I'm glad it's working for you. Now comes the fun part getting everything setup and working the way you want.

stichas wrote on 2021-04-10, 20:26:

Alright It worked.

Cool !
If you ever have the time to take the motherboard out of the case and take a nice photo of it, that would be grand ! 😀

Good news everyone. SO basically the damaged MB was quite a decent donor. It had 16 MB ram. So I added this to the ICL ERGOPRO C4/33
It is working and registering all 20 MB of RAM. Just need a more decent HDD or IDE to CF adapter. Due to noise
Also found a manual that mentions these models
https://www.manualslib.com/manual/920488/Fuji … l?page=1#manual
It seems this is Fujitsu before the Siemens merger.

And below are the MB photos. Sorry but all I have is an iPhone to take these with 🙁 But the chip labels are visible.
The photos are 6 - 8 MB in size. But the forum resizes them. Maybe there would be another good place to upload these (hmm)

And the Reiser / ISA expansion card and other side of MB

Thank you very much ! I've added the best photos here
http://www.win3x.org/uh19/motherboard/show/3025

I also have one of these ICL Ergo Pro C4/33 slimline computers, and no, there was never a cache module installed.
Bit of a shame since it could be a nice upgrade path with a DX2 66 MHz.

This is it:

Actually I may have wrongly identified, C4 without the /33 looks the closest:
https://stason.org/TULARC/pc/motherboards/I/I … 4-V-SERIES.html

These are close but C4/33 has more RAM slots and E250 has a battery that isn't mounted on the plain C4:
https://stason.org/TULARC/pc/motherboards/I/I … -25-D4-33D.html
https://stason.org/TULARC/pc/motherboards/I/I … GOPRO-E440.html

Kasreyn wrote on 2021-07-16, 18:32:

I also have one of these ICL Ergo Pro C4/33 slimline computers, and no, there was never a cache module installed. Bit of a sham […]
Show full quote

I also have one of these ICL Ergo Pro C4/33 slimline computers, and no, there was never a cache module installed.
Bit of a shame since it could be a nice upgrade path with a DX2 66 MHz.

This is it:

You till will get a speed increase with a 486DX2/66 if you have one available.

From my experience the only costs to performance increases for good DOS game play are
486sx33 upgrade to 486dx2-66
486dx2-66 to Pentium Overdrive 83mhz.

Other wise you are just waisting your time and MONEY because you really need a Pentium class CPU for good DOS game play performance
That will NOT stutter or hesitate.

Also on the 486 I found that if you have miss match RAM speed sticks it will cause your 486 computer NOT to perform
At optimal performance and you will get more stuttering and hesitation.
I prefer to use FPM -60ns RAM in my 486 computers. 8mb to 16mb is enough for good performance on a 486.
For DOS game play you only need 8mb fo RAM. But Windows 3.11 will make use of up to 32mb of RAM.
So more than 8mb. Of RAM is only needed if you are going to run MS-Windows.

Caluser2000 wrote on 2021-07-16, 20:42:

Kasreyn wrote on 2021-07-16, 18:32:

I also have one of these ICL Ergo Pro C4/33 slimline computers, and no, there was never a cache module installed. Bit of a sham […]
Show full quote

I also have one of these ICL Ergo Pro C4/33 slimline computers, and no, there was never a cache module installed.
Bit of a shame since it could be a nice upgrade path with a DX2 66 MHz.

This is it:

You till will get a speed increase with a 486DX2/66 if you have one available.

Agreed DX2-66 was the best upgrade path for several years

A lot of later 486 games are much more playable even with ISA video just need to temper your expectations for how far you can go