well in terms of cpu OCing there is now program for it.
Its all in your bios
http://www.dfi-street.com/forum/showthread.php?t=20823
My favorite guide out there, iv been now treating it as my relgion.
In terms of GPU OCing there is a program....sorta
You can download either rivatuner, Coolbits, powerstrip, or ATI tool.
I reccomend riva tuner and ATI tool.
Im not going to explain how to in this post but its fairley easy Im sure a quick google search should help you
What kind of water cooling, custom? Danger Den?