Hi,
I ve a new intel i7 P.c which I intend to use a server.. I ve installed CENTOS 5.5 and It is just not detecting the network card!!
I get the following error -
3c501 device eth0 does not seem to be present, delaying initialization

and the MAC address is not present for my system. If I enter the Mac address from the motherboard box it will say - mac address does not match!!

and the network card doesn't start up at boot.

I've googled for the above message and most results say to check /etc/sysconfig/network-scripts/ifcfg-eth0
I've also seen some interrupt and IRQ errors in dmesg. system-config-network reports the IRQ is unknown.

I don't know how to fix this one. Any suggestions from the forum regulars?
WIll just flushing and re installing OS with lan connected work?

It may, but if this is a brand new installation, I'd suggest using the latest CentOS, 6.2. The new system may support the hardware you've got without doing anything else but an installation. At the very least, you'd be on the most current release, which will give you a longer support cycle.

As stated possibly but first post the output of the lspci command so we can see what network adapter is really in your computer.