File C905CTXC.EXE is Diskette #3 of 3 for 3Com's 3C905C-TX and 3C905-TX-M EtherLink Family, 10 Mbps Ethernet PCI Network Interface Card. This diskette, version 5.01, supports 3Com's 3C905C family of PCI network NICs with a common driver set. Drivers on this diskette support: 
NetWare 3.X and 4.X Serverand Client (DOS, OS/2) and NDIS 2 Drivers.
Also includes Utilities, DOS Diagnostics and Configuration Utility

These adapters are in the IBM OBI CTO Portfolio and are assigned IBM P/N's. 
3C905C-TX  =  IBM P/N 01N0533 with an IBM FRU number of 01N0535.   
3C905C-TX-M  =  IBM P/N 01N3699 with an IBM FRU number of 01N3609.