WPF: can't resize window without horrible visual effects

I'm trying to learn WPF (I worked a lot with WinForms but I'm kinda new to WPF) and I have a problem when resizing 开发者_JAVA技巧my windows. There are horrible visual effects.

Here's what's expected: http://data.imagup.com/12/1130871175.jpg

Here's what I get: http://data.imagup.com/12/1130871187.jpg or http://data.imagup.com/11/1130871194.jpg

I'm not doing anything particular, even an empty window is not rendering correctly when resizing ! I do not have any problem when window is maximized. What's the problem ?

Windows 7 32-bit / .Net 3.5 / Raden HD5850

I saw this same issue 2 days ago on our WPF project when someone on our team updated their Catalyst drivers.

Rollback for now; hopefully they'll fix it in the next round.