FM2A88M-HD+ combination with Sapphire RadeonHD4850

DDU used to be called driver cleaner and has been the go to graphics driver uninstaller for professionals for years now.

Hopefully the link I provided will be clean for you.

If it is a fresh install then you can try downloading and running DDU (Display driver Uninstaller) in safe mode to clear out your drivers completely then try an older version with your GPU. The 4850 has not seen any performance improvements for at least the last 8 driver generations so you will not be losing anything going back a version or 2 until you find one that is stable. Also double check the power connections to the GPU as well as make sure it is firmly slotted into the motherboard. 

The 4850 is still a pretty solid graphics card capable of running most, if not all, new games and applications reasonably well. Unless you are a heavy gamer and want better FPS and higher settings in modern titles you really don't need to throw money at a GPU just yet. As a general rule of thumb I determine a graphics card to be outdated when onboard (now on CPU) iGPUs are able to match or outperform them. The reason I look at it this way is because most new games will support higher end iGPUs on the low end of their requirements. 

I hope this helps

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