Just an idea because you didn't mention anything about current configuration: the PC might be a 386, but doesn't the IRQ need to be set to something <8 when the card is used in an 8-bit slot?

I don't know what the current settings are, since the config program insists that there is no card.

Well in this case you'll need to put the card in another computer to configure it correctly (and make sure it's recognized, if you don't know if the card works yet).
It's unlikely that the current IRQ is <8 if it wasn't used in an 8-bit slot before.

AFAIR, the original 3C509 won't work - you need 3C509B.

Grzyb wrote on 2025-08-08, 09:25:

AFAIR, the original 3C509 won't work - you need 3C509B.

Thank you! Can anyone else confirm?

Grzyb wrote on 2025-08-08, 09:25:

AFAIR, the original 3C509 won't work - you need 3C509B.

I came to same conclusion, tried it with a 3C509 and failed..

Now I'm using some random NE2000 compatible in the Commodore PC 10 with the 8088 patched NE2000 driver.
Works as good as my real Novell NE2000 so far (was not cheap, but got it for testing purposes anyway).

Edit: The Etherlink III is better suited for a high-end PC, anyway.
What I think must be considered, also: network business was like graphics card business.
Way back in the early-mid 90s it was about high-performance, low-overhead products.

Ethernet cards were meant to provide excellent throughput in 486 and Pentium class based Novell Netware networks.
No-one spent a single thought about supporting 8-Bit slots and XTs.
Even low-end diskless stations were 16 MHz 80286 machines or higher.

The only practical reason the no-name NICs did support 8-Bit still was because the original NE2000 design supported both 8/16-Bit operation
and thus made manufacturing of dedicated 8-Bit cards superflous (the NE1000 design).

Edited.

Jo22 wrote on 2025-08-08, 11:31:

The only practical reason the no-name NICs did support 8-Bit still was because the original NE2000 design supported both 8/16-Bit operation

You mean you got a genuine NE2000 working in 8-bit slot?
What card model exactly?

I know that some NE2000-compatibles do work, but thought that originals don't...

alexshendi wrote on 2025-08-08, 11:27:

Grzyb wrote on 2025-08-08, 09:25:

AFAIR, the original 3C509 won't work - you need 3C509B.

Thank you! Can anyone else confirm?

Yes, these are certainly different cards. But I don't believe I've used the 3C509 myself, and certainly not in an 8-bit slot. But I can tell you if you search this forum or the net, quite a few people buy 3C509's off ebay thinking they are compatible like 3C509B and find out they don't work. So I've heard this happen alot of times.

Grzyb wrote on 2025-08-08, 12:46:

You mean you got a genuine NE2000 working in 8-bit slot? What card model exactly? […]
Show full quote

Jo22 wrote on 2025-08-08, 11:31:

The only practical reason the no-name NICs did support 8-Bit still was because the original NE2000 design supported both 8/16-Bit operation

You mean you got a genuine NE2000 working in 8-bit slot?
What card model exactly?

I know that some NE2000-compatibles do work, but thought that originals don't...

Thank you for your interest. I have to check. I'll edit this post once I know.

I have both 509 and 509B cards and the issue intrigued me so I just tested that. The mobo is 386 class but with 486DLC CPU on it, in case it matters.

3C509-COMBO: Detected by 3C5X9CFG.EXE but fails the testing sequence right at step 1, register access
3C509B-C: Detected by 3C5X9CFG.EXE, fails the testing sequence on interrupt step due to being set to IRQ 10

This was in 8-bit slot. Both cards work properly in 16-bit slot. I know a bit about EEPROMs on these cards, the model, MAC and all config data is stored there and can be accessed early even before the card is initialized to work. So chances are the non-B model only works up to this point, and any further I/O access must be 16-bit.