RAM: SO-DIMM DDR3, 8Gb, PC3-12800, 1600MHz, Crucial CT102464BF160B
D54250WYKH won't boot after installing SP1 (Win7- 64 bit ).
It said:"no bootable media available", "insert the right boot device".
There were no any problems before installing SP1 (Win7- 64 bit ).
What can I do ? How to solve this problem ? I can always reinstall Windows, but why?