window swapping causing crash

[RSM72]

I got similar problems with IS for some time now on my former gtx 480 and current gtx 580. One thing I noticed is that graphical glitches occur alot more often if the card is operating near its physical memory limit. Thus I see almost no crashes/glitches while instancing or questing in remote areas (memory usage on the card is considerably lower there) but as soon as the team enters high population areas (eg. Orgrimmar) the problems start.

Toggling vertical sync was one of the fixes I discovered (either switching it on and off worked). Currently as a temporary workaround I hotkeyed the macro "/console gxRestart" to reinit a clients graphics engine (/ReloadUI works too but gxRestart is much faster). I even got a key to do that on all clients so I wont have to restart the clients every so often. The only downside to this is that all clients end up full size on my main screen and I have to cycle through them once so the slaves move to the secondary screen.

I got the 580 replaced by my retailer and I replaced the systems memory but the problems did not go away.

EDIT: can you try to describe what kind of graphical glitches you see? All effects occur instantly after swapping clients - what I have seen so far is:
- flashing interface on a slave client
- master client stuck at 25% size and not responsive
- master client overlayed with several 20-25% sized copies of itself most of the time flashing interface on top of that
- random bitmaps on parts or the whole master client (while it renders fine as a slave if i put it back there)

- random triangles originating from the center of the character (depending on the viewing angle - but I think this is a bug in wows DX11 engine)