Win7 computer boot display reboot and select proper boot device how to do

1. First try to press F2 to enter the BIOS interface on the keyboard. If you can go in, you can manually modify BOOT ORDER. If you can't get in, you may be infected by viruses. Other reasons may not be excluded. You can change the CD-ROM drive. Give it a try.
2, may be a problem in your system boot part, check whether the hard disk boot is set in cmos, if set, then it is likely that the hard disk has a problem, use the CD to boot and check.
3, may be the computer can not detect the hard disk (can not detect the symptoms of the hard disk: IDE does not display the hard disk information when booting)
Hard disk detection failed:
1) motherboard BIOS does not remember To the hard disk information, if your system date is not correct, then it may be the reason
method: replace the BIOS battery, re-enter the BIOS to detect the hard disk.
2) The quality of the IDE cable is not good or the plug is not secure.
Method: Change an IDE cable or plug the IDE cable into another IDE slot of the motherboard. Do not connect the cable of the hard disk with other IDE devices. Optical drive, separate two IDE lines, correctly set the master /slave disk;
3) the hard disk failure, you may need to replace one;
4) If your computer can detect the hard disk every time and can not enter the system Then, you can only re-format the hard disk completely, and then reinstall the system.
There are two main types of BIOS: AWARD BIOS and AMI bios
1. AWARD bios sets the hard disk boot
Press F2 to enter the BIOS, use the arrow keys to select Advance BIOS Features and press Enter to enter the menu. Press the First BOOT Device button to enter and use the arrow keys to select HDD-0 and press F10 to save and exit. This will change the boot mode to hard disk boot.
2, AMI BIOS settings hard disk boot
After entering the BIOS, use the arrow keys to select BOOT to select the first BOOT Device Priority, then select 1st BOOT Device in the submenu to change the item to the corresponding hard disk.