AS SALAM O ALAIKUM

Ma jab apna computer ON krta hun, tow aik ERROR "DISK BOOT FAILURE, ENTER DISK AND PRESS [ENTER]" ye show hota ha,, jb k koi disk ni ha, windows b normally install hain, na hi many boot lagaya ha, SETUP ma ja kr b chek kia koi changes ni hain..

YE PROBLEM KBI KBI HOTI HA,, 2 OR 3 times restart krnay pe phir normally OPEN hota ha,,,

KINDLY HELP ME.....