Laptop keeps rebooting on boot screen

Hi

The laptop is MSI CX640 it runs windows 7 .

The problem is that when I start the PC it displays a screen with the MSI and Intel logos then goes to to a black screen and reboot. I cant enter setup or boot from any other device. The keys do nothing, usually the keys a promted on the first screen but they arent.

I think the issue as something to do with the computers battery dying when in sleep mode.

Any ideas how to fix this problem?