You can go to system settings, and power management.
Or from a command line, "setterm -powersave off -blank 0" (though this one wont survive a reboot)
You can also update your grub to include the following:
"acpi=off apm=off" to the GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub., the run "update-grub"
and reboot. (this will make it perm)
Hope that helps