Could anyone please help to resolve the below problem.
I installed RHEL5.5 in my desktop.But when i try to activate the ethernet connection then it gives me the error.
#ifup eth0
e100 device eth0 does not seem to be present, delaying initialization.
I spent 2 days for the above and go through with several suggestion found by googling. But no luck.
Please help me.

Below are the some command & result which i executed on my machine.

[root@localhost ~]# ls /sys/class/net show
ls: show: No such file or directory
/sys/class/net:
lo sit0
[root@localhost ~]# lspci -vv | grep -i net
00:19.0 Ethernet controller: Intel Corporation Unknown device 1503 (rev 05)
[root@localhost ~]# dmesg | grep eth
You have mail in /var/spool/mail/root
[root@localhost ~]#
[root@localhost ~]# uname -a
Linux localhost.localdomain 2.6.18-194.el5PAE #1 SMP Tue Mar 16 22:00:21 EDT 2010 i686 i686 i386 GNU/Linux
[root@localhost ~]# lspci | grep -i eth
00:19.0 Ethernet controller: Intel Corporation Unknown device 1503 (rev 05)

[root@localhost ~]# lspci
00:00.0 Host bridge: Intel Corporation Unknown device 0100 (rev 09)
00:02.0 VGA compatible controller: Intel Corporation Sandy Bridge Integrated Graphics Controller (rev 09)
00:16.0 Communication controller: Intel Corporation Cougar Point HECI Controller #1 (rev 04)
00:19.0 Ethernet controller: Intel Corporation Unknown device 1503 (rev 05)
00:1a.0 USB Controller: Intel Corporation Cougar Point USB Enhanced Host Controller #2 (rev 05)
00:1b.0 Audio device: Intel Corporation Cougar Point High Definition Audio Controller (rev 05)
00:1c.0 PCI bridge: Intel Corporation Cougar Point PCI Express Root Port 1 (rev b5)
00:1d.0 USB Controller: Intel Corporation Cougar Point USB Enhanced Host Controller #1 (rev 05)
00:1f.0 ISA bridge: Intel Corporation Unknown device 1c5c (rev 05)
00:1f.2 SATA controller: Intel Corporation Cougar Point 6 port SATA AHCI Controller (rev 05)
00:1f.3 SMBus: Intel Corporation Cougar Point SMBus Controller (rev 05)
01:00.0 PCI bridge: Integrated Technology Express, Inc. Unknown device 8892 (rev 30)

[root@localhost ~]# lspci -nnk
lspci: invalid option — k
Usage: lspci []

-v Be verbose
-n Show numeric ID‘s
-b Bus-centric view (PCI addresses and IRQ‘s instead of those seen by the CPU)
-x Show hex-dump of the standard portion of config space
-xxx Show hex-dump of the whole config space (dangerous; root only)
-xxxx Show hex-dump of the 4096-byte extended config space (root only)
-s [[[[]:]]:][][.[]] …read more
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