Bad performance with ISBoxer

[Pallarfo]

Did some more testing, facing walls: 60fps, facing crowd it drops.
Checked everything Khatovar and Sam said, everything is fine.
Did reinstall Windows yesterday and am now downloading everything and start from scratch.
Lets see what happens then.

[Lax]

Did some more testing, facing walls: 60fps, facing crowd it drops.

That sounds exactly like in-game graphics quality settings.

Something to remember: ISBoxer virtualizes your Config.WTF file, meaning it has a different copy of Config.WTF for each Character you launch/play through ISBoxer. So when you launch a single character without ISBoxer, you may be loading it with different graphics settings than with ISBoxer. So make sure that when you're checking them, you do it when launched through ISBoxer!

You can reset any given Character to use the base config.WTF by going to your WoW\WTF folder, find the "Config-my character.WTF" file, and delete it. The file will be created from the main Config.WTF again when you launch him.

[Pallarfo]

Double post.

[Pallarfo]

That sounds exactly like in-game graphics quality settings.

Only happened when the game runs through ISboxer, not when started with the .exe.
but:

Hi all,
It is solved. For now it seems.
Destroying all the wows and putting it back to DX9 like Lax (and others) have suggested did the trick.
No idea why, yesterday putting it back to DX9 did not solve it. Maybe a mix of something. No idea.
Regarding the screens, no unplugging on the gfxcard site has been done, only moving from right to left physically.
They remained at the same slot.
I'm happy it seems to work again, (50fps yippie), but the solution seems questionable.
Thank you all for thinking along!
Lets roll into Pandarian!