Does Amarok in Linux have an option to load a complete WAV file into memory and play from memory? Some programs in Windows use it to avoid "disk interference" during playback.

That simply depends on your amount of memory available at that very moment. Linux distributes memory more dynamically than Windows does. But I fail to see what "disk interferences" you would want to prevent with that TBH.

The theory is that while playing from harddisk the spinning of the HD gives interference in the powersupply and that is unwanted.

A related question is: if I only use this specific pc for audioplayback, do I need a swapfile?

@audiofanatic: Your system should always have a swap partition available for optimum memory usage.

Thanks for all your help. I will keep on trying to find a solution, does Linux "natively" use something else as cuesheets?