Ethernet card driver installation

We have recently installed a 6.2.1 on an Intel 945 chipset motherboard. The OS didn’t see the onboard ethernet so we found an old 3comm 900 (3C900) PCI ethernet card. Disabled the onboard chip from BIOS and reinstalled the OS. Eventhough the driver file for this card comes with the OS installation it didn’t find it during the installation. I tried to install it manually but didn’t really know what commands needed to be inserted in which files.
I killed the existing Io-net and called it again with the correct driver. But couldn’t keep the IP at bootups. net.cfg was flushing at bootups. I had to fix the IP from the sysinit as well. Finally I got it to work. But now telnet and ping to this computer sometimes doesn’t work at all sometimes it takes 2-3 minutes before I get the initial response. I must have done something wrong at the installation. Any pointers would be greatly appreciated.
Why wouldn’t the OS install the card if it has the driver for it? Could this be related to the chipset or BIOS?
Thanks.

is your network using DHCP? When you say couldn’t keep the IP at bootup, do you mean you wanted static IP or when you boot up you always need to restart the network driver?

QNX (and Linux, FreeBSD as well) may cause trouble with the DNS list resolv.conf, when dhclient overwrites it. I’ve had this with Debian as well as QNX, and the solution is the same. It can be found here: forums.debian.net/viewtopic.php?t=7239

If you experience this same problem when using IPs not domain names, then ignore this post.