This bug has been copied from bug #554525 and has been proposed to be backported to 4.8 z-stream (EUS).
Committed in 89.0.24.EL
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2010-0394.html
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: A regression prevented the Broadcom BCM5761 network device from working when in the first (top) PCI-E slot of Hewlett-Packard (HP) Z600 systems. Note: The card worked in the 2nd or 3rd PCI-E slot.