I only see a black screen

[Anonymous]

Hello everyone,
When i open the Archicad 15, i only see black screen (as seen screenshots) on the workspace. But i can see the workspace normally when i do pan or rotate view.
My hardware and OS:
Windows7 64bit
6gb ram, ati radeon hg5570 4gb gpu, intel core i5 2.9 cpu
Screenshots:
The problem:


When pan and rotate:


How can i solve this issue?
Thanks.