I agree that using older versions of anything may not be a good idea. Two people with same issue with DHCP.exe made me think about:
newer BIOS versions with dropped micro code, newer video drivers that give worse performance/crashes, etc so was just a thought. As I said "(doubt that will help but can't hurt...)"

kepak wrote on 2024-05-04, 12:33:

All utility software detects this card and i can change settings

This is a good sign and would seem to suggest more of a driver issue then hardware.

I'd probably stick with Win95 for troubleshooting, nice easy modorn-ish GUI
Which drivers are you using? I don't have any of the cards listed so can't give any known to work driver, but this here is a list for the complex card.

https://www.network-drivers.com/companies/237 … thx=9&bng=7&o=2

Also what are you using for a DHCP server. There have been some reports of newer devices not working with 10Mb cards.

At this point, I suspect some weird incompatibility between that machine and NE2000-style cards.
It seems logical to try something completely different: 3Com, Intel, SMC...

Grzyb wrote on 2024-05-06, 05:37:

At this point, I suspect some weird incompatibility between that machine and NE2000-style cards.
It seems logical to try something completely different: 3Com, Intel, SMC...

I think the same at the begining of this thread. I decided not to buy another card, i just pass networking this PC.

Do you have all voltages needed for that card on your ISA bus? Not sure what version you have of that card, TP or Coax?
check e.g. https://www.arstech.com/install/cms-display/s … upplyneeds.html

Rwolf wrote on 2024-05-06, 12:30:

Do you have all voltages needed for that card on your ISA bus? Not sure what version you have of that card, TP or Coax?

Ethernet cards only need +5 V.
Yes, Coax transceivers need 9 V, but even this is provided from the +5 line, using a DC-DC converter.

Overall, if an SB-compatible sound card works, an Ethernet card should work as well.