This morning my dual monitors were not recognized; both displayed same thing. The higher resolution was not supported. The monitor manufacturer says problem is with display adapter ATI Radeon HD 4200. There is no indication that the PC was re-booted.
OS: Windows 10
Monitors: Dell SR2220L(Digital)
This has been caused by a Windows 10 update. You can find a potential solution here : ATI Mobility Radeon HD 3670 Not Working With New Windows 10 FCU Update
thanks
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This has been caused by a Windows 10 update. You can find a potential solution here : ATI Mobility Radeon HD 3670 Not Working With New Windows 10 FCU Update