Ok, tried messing around with a few settings...and presto it worked...but it was zoomed in. Right click screen > Display Settings > Display > Customize Your display screen - it was zoomed in at 150% by default. WTFH. Nice default setting win10/nvidia...
And Alpha works pretty smooth.

I gotta say, with older age, being a PC whiz like I used to be is getting harder and harder all the time...
