Yes, there will be no more updates for your HD 6xxx series AMD card. The only way you MAY get an update is thru Windows Update to make the Graphics card compatible with the current version of Windows.
Otherwise, you are stuck with the old AMD driver until you upgrade your card to one that is still supported by AMD or Microsoft makes your card incompatible with any future Windows version.
As to your current problems, it is possible your card is failing. May want to test it out with a Diagnostic software. I use OCCT which stresses the Graphic card while checking for GPU errors (need to check GPU ERRORS box). There are others that people suggest that may be more suitable. OCCT is freeware.