# yum install yum-priorities



# rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt


# yum install http://packages.sw.be/rpmforge-release/rpmforge-release-0.5.2-2.el6.rf.x86_64.rpm

# yum check-update

# yum search nvidia

# yum install nvclock.x86_64

# yum remove xorg-x11-drv-nouveau.x86_64



# reboot



reboot complete and press enter key