I recently was tasked to create a thin client type device and needed to disable all power management features. I found it to be more convoluted then I expected, so here are the options I found. In the end, the options in bold were all I needed to disable the screen blank power management and all screen savers in gnome.

Disabled the screen blank during a text based login:
Added consoleblank=0 to the kernel line in /boot/grub/menu.lst
Added /usr/bin/setterm -blank 0 to the /etc/rc.local

Should add to user’s .bash_profile or other user specific login file:
Disable all Xorg power management:
/usr/bin/xset s off
/usr/bin/xset -dpms

Disable screensaver settings on Gnome 2 – CentOS 6
yum remove gnome-screensaver gnome-power-manager -y

References:

http://www.cyberciti.biz/tips/linux-disable-screen-blanking-screen-going-blank.html

http://www.mythtv.org/wiki/DPMS