Dimensional fonts artifacting

I have installed Rhino 6 on Virtual Box, Windows 7, 64Bit.
It is working great except fonts at dimensions are not shown fully. See the screenshot below.
When printed it is ok. Does anyone have idea how to fix it?
I have tried all the options on dimensions, texts, settings screen and 3d support in windows – nothing helped.
I understand that VirtualBox is limited, but maybe there is solution for fonts…