i have an alienware m17x R2 and when i swith to discrete gpu cards the gtx260m after some use i have black screens its happens after some time also in gaming, but sometimes its runs fine, i trid upgrading the drivers but the problem does not solved,i dont know if a bios upgrade will help, i dont know what is the proble, can someone gave me some hints pls? maybe its overheating but the system has never shutdowned so i dont know if its overheating, i think maybe on of the gpus is fualty