no service Lenovo

I bought a Lenovo Z750 laptop brand new 3 June and from day 1 the machine was giving me no boot errors and switching itself off it was extremely slow and programs kept crashing with not responding errors. I contacted Lenovo technical support, which in itself will drive you insane as they kept dropping the calls and it is almost impossible to hear the technician on the other side. They had me reformat the machine, meaning i had to backup all my work and lost more work time. The machine kept crashing, phoned them again and had to go through same procedure again, by now i lost a weeks work, they informed me to take machine in to Partserve for analysis, it was there another week before they let me know there was nothing wrong with it, i refused to take the machine back and with the help of a person at Partserve got the machine booked back in with another technician who eventually found the problem to be with the hard drive. Now Lenovo and Partserve is in an email battle re the machine and the problems not picked up from the start and i am still without a machine. I haven't heard a word from Lenovo at all, impossible to get someone in charge to speak to.