Does anyone know or it is possible to get a PWM signal of 0-10v out of mach3, until now i get max. of 3,22 v, so my spindle is only getting max 1/3 of the speed!!? ???I use a thirdt party breakout of Granite and a second parralelport. Is my PC able to create 10v at all?

Not directly, but there are spindle drive boards out there that connect either via the PP or modbus.  Peter Homann sells both varieties I think.  Some break out boards have that built in.