XO-1.5 video rendering not always smooth

[Mikus Grinbergs]

> The support for the (brand new) video hardware
> found in the XO-1.5 is still in teething stages -- this is why the
> performance is bad. We've got the appropriate tickets open but it will
> take us some time to get there.

I searched, but did not find tickets specifically addressing "poor
motion" nor "cursor flicker" on XO-1.5.  Opened #9921 to make sure.

mikus