So I upgraded my pc to an i5 based system. Problem is both on samplitude and Reaper, when cpu only hit %30 (with upsampled plug-ins like voxengo and melda production) playback problems start. On Samplitude it writes dsp= 100% while cpu is still low.
But its interesting this doesn't happen with Nebula, I insert few 10 kernel presets and everything works normal. Anyone had similar problem before? I wonder if its a bios related thing.