X51 auto shutdown problem

I bought an x51 for my son as a christmas present thinking that the alienware name would represent quality. The machine simply does not work, it powers up and then after approx 50 seconds it powers off. So after 5 days the Christmas present has been completely unusable. My son is very upset and can not grasp why this has happened due to his mild austistic tendencies. A "service engineer" has been today to replace the graphics card which has made no difference. I now know that Dell contract out these home visits as he was from another company. Dell also do not check on the quality of training of their subcontractors as the "service engineer" did not use an anti static wristband when changing the graphics card. I was a little shocked at that! I have been phoning tech support after the "service engineer" visit but nobody ever answers. I have spent at least 1.5 hours on hold and will be pursuing Dell for reimbursement for at least the cost of phone calls and potentially my time. I consider this to be very poor customer service. I have been phoning tech support again today, could someone tell me why I have to listen to 10 different options only to be told at the end that tech support don't work at the weekend ? Since the machine is still not working and even after a visit from the "service engineer" there is no progress, I can not recommend the x51 or any Dell product to anyone. In summary, it is a bad product, it can not have been factory tested before shipping, Dell support is awful and my boys christmas is ruined. Thanks Dell.