Ok, last week i had problem with this card which crash on most game except RTS game. I have tried almost every fix on how to get rid of "Display Driver Stop responding and have recovered".

Then yesterday i underclocked (did i said it right) my GPU clock from 900mhz to 850 mhz. And the problems disappeared YAAYYYY... 

it's not such a big deal cause i didn't notice a drop in performance, but of course it will hamper any option for me to OC my card.

Now my question is, what causing this ? 

Any responds will be appreciated, thanks.

Motherboard:  Gigabyte GA-H61M-DS2 intel Socket 1155 
CPU:  intel i5 2400 (3.1Ghz,C6Mb,Lga1155) intel LGA 1155 
RAM:  1 stick of Kingstone KVR1333D3N9/4G 4Gb PC 1066 DDR3  
Video Card: XFX HD 6870 1Gb 256Bit DDR5 HD-687A-ZDBC     

PSU Seasonic 650W SS-650JT  

Hard drives: Seagate 160GB (i know it's small, but give me a break)  
Number of fans present: 3 (2 on GPU, 1 on CPU), 4 if you  count the air conditioner.

Operating System : Window 7 Ultimate 64-bit

Video Card Drivers in Use ( and tried ): 12.4, 12.2, 12.3 (ended up using 12.3) 

Apps/Games causing issues ( and if they've been patched ): well, actually any first person / third person game

Other things tried: Change the Tdr value, uninstalling CCC, underclocking GPU clock, (sunday i will try to use different ram and PSU).  

Gigabyte GA-Z77X-D3H, Intel i5 3570k,  2x4 GB Kingston, XFX HD 6870, Seasonic M12II 850W, Windows 7 Ultimate x64, Seagate 500GB, Seagate 2TB

First let me say, your English is good. However...before you can expect any kind of sane guess as to what your issue might be caused by...you will have to read FAQ (at the top of the page) and comply with the suggestions there in..and all. If that is impossible, read the "Read This Before Posting" (which Ruby thought was sufficient).

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