How to enable two intel lan cards in red hat linux 7.0

["subashini.P" <psuba@xxxxxxxxxxxx>]

Hi all,
           I am having intel L440gx motherboard which is having onboard
lan.it is working fine.My aim is to use two lan cards in a single
system.So,i put one more intel pro lan card .When i disable anyone of
these,it is working fine.When i enable both these cards,on board lan is
only working.The addon lan is not working.Pls give me some solution.I
can be able to configure both the cards and able to see both the modules
in netcfg.Pls suggest how to ping from both the cards.
Thanks in advance.
Rgds,
suba