I found this and cant believe that AMD would have drivers out there that crash because it's switching from idle state.
I found this in the microsoft forums and the issue resolved my problem with Super Street Fighter 4 Arcade Edition
I suggest AMD resolve this issue so that we do not have to edit xml files to resolve issues with games.
I am a first time poster here in 3d Guru, long time stalker .... love the reviews and have read on so many issues which were solved on the forums... I thought it would be a good time to give back to the community which helped me for so many years...
I recently planned on building a new rig cause I moved into a new apartment and only had a laptop which could not fulfill my gaming needs. I am a student so my PC was not the best of the best but preety good for a student. So I faced some troubles in my build, the first being a defective mobo and then the infamous 7870 problem. I searched the internet for the last two days , trying to find a solution to the problem , at the same time I did not want to RMA (didnt have the original package). However I cam across a forum which tried to fix the problem but the explanation was not so good and did not relate to the 12.7 beta driver which I think every 7870 user has installed. So let me give you the steps for this fix and I hope it works, so far I havent had any crashes playing Diablo 3, BF3, Killing floor 2 , all on maximum settings.
Okay so two things are causing the crashes:
1. 2d clocks ( I guess this is the clocks of your gfx card wen ur in the desktop and not running any games)
2. ULPS ( don' know if helped me but just in case)
Steps to increase 2D clocks:
1. Go to CCC and enable over drive.
2. Put your fan speed up to 100% (just to be careful   and the Power slider to +5% (just in case )
3. Now close CCC. Open up task manager.
4. Go to the Process Tab and delete CCC.exe and MOM.exe and any other process related to CCC or ATI
5. Make sure you can see hidden files and go to the following directory, C:\Users\(Username)\AppData\Local\ATI\ACE\profiles .xml and open it using notepad
6. Look for :
(x0000 is your idle-state core clock. Change the value to the one's in "Want_1")
(y0000 is your idle-state memory clock. Change the value to the one's in "Want_1")
I don't exactly remember but there should be a property related to the voltage make sure that is also the same value as "Want_1" corresponding to the property.
7. Click save in note pad.
8. Open CCC.
9. Using GPU_Z or similar software see the current clocks of your memory and core, it should be at the maximum level.
Now try playing a game or running a program which causes the black screen it should not take place....
If it is try disabling ULPS by downloading this exe from this website...
Restart your computer and see if everything is working alright...
So from mhy understanding, your 7870 when playing games sometimes downclocks to the 2D clocks (which u just changed) this results in the game freezing due the sudden loss of processing power. I am not so tech related so I might be wrong but this fixed worked for me so far, I will post if anything comes up later on. And if it works please post a reply so we can give this fix to other users who face similar problems.
Experiment with the settings so you can reduce your idle clocks without crashing in the game and also reducing the fan speed.
Dont forget to change your power settings to High performance (again just in case