output of
lspci would be helpful
Is there a specific reason you didn't install RHEL 5.2 or Centos 5.2 ?
Version 5 has been out for over a year, and would have much better hardware support ..
Code:
# Red Hat Enterprise Linux 4 (Nahant), 2005-02-15, kernel 2.6.9-5
* 4.1, also known as Update 1, 9 June 2005[8], kernel 2.6.9-11
* 4.2, also known as Update 2, 5 October 2005 (Release Notes), kernel 2.6.9-22
* 4.3, also known as Update 3, 7 March 2006 (Release Notes), kernel 2.6.9-34
* 4.4, also known as Update 4, 11 August 2006 (Release Notes) kernel 2.6.9-42
* 4.5, also known as Update 5, 1 May 2007 (Release Notes) kernel 2.6.9-55
* 4.6, also known as Update 6, 15 November 2007 (Release Notes) kernel 2.6.9-67
* 4.7, also known as Update 7, 24 July 2008 (Release Notes) kernel 2.6.9-78
# Red Hat Enterprise Linux 5 (Tikanga), (Release notes) 2007-03-14, kernel 2.6.18-8
* 5.1 (also known as Update 1), (Release Notes) 2007-11-07, kernel 2.6.18-53
* 5.2 (also known as Update 2), (Release Notes, single file) 2008-05-21, kernel 2.6.18-92