alienware 17r2

Hey, my alienware 17r2 have stopped booting win8. every time i try to turn it on, it either stops on the alienware logo,  or it gets a blackscren with some options. and a bluescreen where i can chose to turn of computer or reapair computer. I have tryed to use the usb, with win8 rapair on it. it did work but when i did turn of the pc again the sameproblem did come Back. 
i realy dont know what to do?? i have tryed everything. i feel that i am very disepointed on the pc.. i have only had it for 1 month and it have alrady stoped working. 
English is not my 1. languag so sorry for bad English.