Some interesting comments, which sparked these questions:
1) Has anyone done a CPU utilisation comparison between the Intel Pro cards and the same class 3com cards on a 486? What was the outcome?
2) I beleive some of the 3com cards I have are PCI 2.0 compliant, while some are PCI 2.1 compliant. What PCI specs do most of the Intel cards adhere to and is this something we should be cognizant of when selecting an Intel card? Will a PCI 2.2 spec card work, for example? Both the PCI 2.0 and 2.1 compliant 3com cards worked in my UMC 486.
3) Does anyone have any positive accounts of Intel network cards working more reliably at 40 MHz compared to 3com cards? I beleive all PCI 2.2 spec cards must operate up to 66 MHz, but I could be wrong. This goes back to 2), will a PCI 2.2 spec card work in a socket 3-class motherboard?
4) It was noted that the 3com cards utilise more CPU than their Intel counterparts. Could you test your throughput with a stop watch using your Intel card? This is what I get for a PCI 3Com 3c905C-TX-M 10/100Base-TX card:
Sending a 30 MB file from a PIII to the 486, whereby the PIII initiated the transfer: 1.54 MB/s
Sending a 30 MB file from a PIII to the 486, whereby the 486 initiated the transfer: 2.37 MB/s
Sending a 30 MB file from the 486 to the PIII, whereby the PIII initiated the transfer: 3.20 MB/s
Sending a 30 MB file from the 486 to the PIII, whereby the 486 initiated the transfer: 1.37 MB/s