So currently i am using MSI afterburner to overclock my 6870 to 950/1200. Some reason my reference model didn't have adjustable voltage unless i do it in BIOS. That isn't the problem though, I'm trying to figure out a way to keep my card overclocked without having to open afterburner and apply my profile every time i start the computer up.
As for the CPU fan, i can't find a way to set the fan to go up in increments depending on the temperature of the chip like Afterburner has for my graphics card. The only thing i can do is have a preferred CPU temperature, and a preferred CPU fan speed, if the temperature goes past the mark it just kicks all the way to 100% it doesn't even slowly rise.
More about :6870 overclocked shutdown held cpu fan
In afterburner you need to go into the settings and check the box that says start Afterburner with windows (or something like that). Then you need to check apply overclocking at windows startup on the main screen. Also make sure you are using the latest version of Afterburner.