Ethernet drivers in SL 5.4

[Elio Fabri]

Hi, Ihave installed SL 5.4 on my new desktop and have a problem with 
internet drivers.
The adapter integrated in the motherboard is a clone of 3c501. Linux 
tells me that non driver is present.
I have also mounted an old card, a clone of ne2000, and get the same 
message.
The kernel version is 2.6.18-164.2.1.el5
What can I do?
Thx
--
Elio Fabri