The solder bridge will make the chip working in LPC mode. Not sure if it's the culprit but I would get it removed asap.

The Intel 430NX chipset supports PCI 2.0, while the VIA page for the VT6421A mentions "Complies with PCI Local Bus Specification Revision 2.2". Possibly this could be another reason (besides that solder bridge)?

SW-SSG wrote:

The Intel 430NX chipset supports PCI 2.0, while the VIA page for the VT6421A mentions "Complies with PCI Local Bus Specification Revision 2.2". Possibly this could be another reason (besides that solder bridge)?

Yep, that is. It will not even work reliably in 440BX mobos cause these are only PCI2.1. VT6421A needs MSI/MSIX support, which is only available as optional feature in certain PCI v2.2 chipsets, and only was made mandatory in PCI v3.x chipsets. That generally means Pentium4 and AthlonXP Barton compatible motherboars and up.

As a sidenote, this is also the case of many USB2.0 cards, certain Terratec audio cards with Envy24 chipset, TvTuners based in last Conexant chips and some cheap PCI to Cardbus adapters using versions of TI and Oxford chipset. These will not work in anything older than P4/AthlonXP Barton compatible motherboards.

@lazibayer

I removed the solder bridge and it didn't help.

@SW-SSG & hyoenmadan

I'm not sure it is a PCI problem with this card. At least I hope not. I've read of people using VT6421A cards on 486s with PCI 2.0 and they had no problems. The VIA spec sheet says it's compliant with PCI 2.2, but that does not mean that it isn't incompatible.

I have a SIL3114 card that works perfectly on this computer and it is PCI 2.3 compliant. A Promise Fasttrak PCI 2.2 compliant and works fine. And a Promise SATA300 Tx2 Plus that is 2.3 compliant and works perfectly.

These cards are dirt cheap. I'll get a couple of different models and try them out. In the mean time I'll install the Windows drivers and try Linux to see if I can read the any attached drives.