Typically, the USB support is enabled in BIOS by default. But if she for some reason was disabled, you must activate it. To do this, when the computer starts enter the BIOS, the entrance most often by pressing the Del key. As manufacturers of computers in this case do not adhere to a single standard, enter the BIOS can be done by pressing Esc, F1, F2, F3, F10, or Ctrl + Alt + Esc.
Going into the BIOS, find the section Integrated Periphirals. In it look for the line USB Controller and set its status to Enabled ("Enabled"). Save the changes by pressing F10 or going to the main window by pressing Esc and selecting Save & Exit Setup. In the resulting window you will be asked to confirm the change, enter Y and press Enter.
More often the user encounters the need to connect a USB flash drive as such and for download from her computer. For that many computers has the option of selecting the boot menu, usually it is called when you start the computer by pressing one of the keys: F8, F9, F10, F11, F12. The specific key depends on the motherboard.
Selecting the desired boot device, in this case USB. Boot the computer will be implemented with the stick, but on the condition that it have the necessary boot files.
If you can't find the boot menu, select the pendrive as the boot device can be performed directly in the BIOS. To do this, enter the BIOS and find the tab with the strings First boot and Second boot – that is the primary boot device and secondary. In the fields next to these rows contain the current settings. Change them as desired – for example, set the primary boot device USB drive and a secondary hard disk. Save the changes as described above.
Remember that if you install the operating system from a flash drive or CD and chose the boot device in the BIOS, not in boot menu, then after the first automatic reboot Windows should re-enter the BIOS and return to booting from the hard drive. If this is not done, work the startup from a flash drive or CD-ROM, and Windows will again start the first stage of the installation procedure.