Mmm...
well the problem resides mainly on your graphics card, but hey if you managed to log in and see things nicely...
Outside of game:
Use Planeshift Setup, and go to texture downsampling and move the slider a bit to the right (prior doing this, first try the suggestion that follows, labeled as \"in game\")
In game:
Go to options (second button on the top starting from left) then sound-general. Disable all background sound, effects, etc.
Good luck with it.