hi, many intel motherboard use RTL8110SC network adapter. there is a description on page: http://wiki.centos.org/HardwareList/CentOS5/RealTek/r1000 how one can use r1000 kernel module for centos. unfortunately this driver seems to wrong. if you read carefully realtek download page and the latest source of r1000 (1.07) the r1000 is _only_ for 2.4.x kernel and for 2.6 it's called r8169! the worst thing r1000 seems to working most of the time but at random stage it stop working (eg: after init 4). the source you can download from realtek r8168... is more stable on 2.6.x kernel. i try to add this info to the above page, but it's immutable. in the mean time you can download kernel modules from here: http://www.lfarkas.org/linux/packages/centos/5/