I have a problem with Centos 5 not detecting my realtek 8111b lan chip on a Gigabyte GA-945GM-S2 motherboard. I have found a reference to a new driver from realtek and/or redhat - which has instructions on building the driver. When I go to "make clean modules" I get errors - and it appears to be looking in /usr/src/kernels/... for source files which I don't seem to have in my centos 5 installation. Presumably I need to install some kernel source package. If so - where do I find it? Thanks. Richard.