XAML designer in VS2012/Blend not redrawing properly

Question

I have a dev box with Windows 8 + VS2012 Update 2 on top. Ever since I had this system, the XAML designer has been behaving weird (for Win8 and WPF as well): it redraws only every second time.

Meaning that if I place a control, it does not update (the control cannot be seen, but its outline can be, if I hover over it); but if I place another control, or change the zoom level, or do any other action, then it refreshes. When I do a third action, no update; when I do a fourth action, it redraws. And so on, it is 100% repro-able.

Pretty bad for productivity.

I have the latest drivers and updates, I have loads of RAM (16GB) and a discrete Nvidia video card, I restarted umpteen times, the usual fixes do nothing.

A screenshot: http://sdrv.ms/13BJSof

Anyone with similar experience?

Answer 1

OK, I found a solution - my laptop uses nVidia Optimus (it's a Lenovo W520) and that was the source of this error (amongst others, such as being unable to properly "duplicate" my display to a projector). I solved it by simply turning off Optimus in the BIOS and enabling only the Discrete card.