Why not start-up machine in some cases up

I just installed the machine, sometimes when I boot the host, hard disk lights are bright, that is, do not start up, shut down must also be hard not only to turn off the power of the total, re-boot will do.Let me say that business access to memory Under the eraser rubbed with, I rub, but still will not do.My whole machine in the power play Paishang flying, which is not the normal start-up related to you?