Mercenaries 1 FPS/Sound Problems

[Stunngun]

Greetings fellow gamers,
I have following problem:

Mercenaries´ FPS drops to 12 or 13 when i reach the main menu with the default GSdx 0.1.16 plugin on HW mode (native/8-bit enabled).
With SW i get about 26-30 fps but game ist still unplayable and sound is with both settings absolutely messed up.

I tried many other GS plugins but with the same result.

My PC specs:

CPU: AMD athlon II X4 620 3.26
Gpu: Nvidia GTX 260

PS: YES, I used the search function, but the old topic was not able to deliver any useful information.

Greetings Stunn

[jesalvein]

what do the ee% & gs % say when ou get slowdowns ?
playing from your DVD or from ISO ?

[Stunngun]

what do the ee% & gs % say when ou get slowdowns ?
playing from your DVD or from ISO ?

GS climbs to 100% ee is about 20-30% on SW mode. With 27 fps, graphic bugs, and serios sound issues and stuttering.
at HW mode I got 2-7 Fps and "lavalamp explosion".
I run it from an iso.