Mazak qt200

I've a mazak quickturn 200 here with a 640t contol.

The machine won't start it hangs on the boot up with a replace the hard disk error. So we put in a new hard drive from mazak and no joy.

So they said to replace the NC system, the cost of this part is really high I wanted to know if there was anyone who had this problem and if so what part fixed it.

The machine has been broke down now for 10 weeks so I just went and bought a new machine. To cover this one until it's repaired or scrapped the machine is 2001 or so.

Thanks for any help on this.