As you are not able to uncheck the graphic processor in Lightroom, you can try the following steps:
1.Open the RUN window, type devmgmt.msc, and click ok, it will open the device manager dialog box
2.Select display adapter from the device list and expand it
3.Right click on your Graphic card and disable it and keep the device manager window open
4.Launch Lightroom and try to uncheck the GPU acceleration and restart Lightroom
5.From the device manager windows , please enable the graphic card again.
Let us know if its of any help.
Yes it does thank you - found it after I posted then came back to find my question answered very quickly. Great forum although a pity that Adobe does not make things simpler.
Yes thanks the updated beta driver solves the problems.