One thing I have done to combat the throttling is to create a custom Preset in CCC called Gaming where I set Overdrive to on and changed core and power. I then found the XML file in %AppData%\Local\AMD\ACE and manually edited the XML file under the CoreClock setting want_0 to match the want_1. This completely stops throttling. I also then went in and set the Power back to 0 in the XML file and I am not getting throttling, but I am not sure if this is harming the card in any way. I am not getting artifacts in games or Kombustor. The only problem with this method is that you have to manually set the profile. I guess you could set triggers for each game but that would be a pain.
Since I am getting very high temps 80°C - 83°C I may try to set negative power with default clock of 975mhz and see if I get any artifacts or locks. I am really looking to get the temp down so the fan isn't going crazy b/c anything over 75°C makes the fan go over 50% and it sounds like a hair dryer.
If any of you guys have an interest check out this method and let me know what you get with fan speeds, temps, etc.
i5-3470 w/ CoolerMaster Hyper 212 // 8GB Memory // Gigabyte B75-D3H // PowerColor 7870 EZ