PLEASE HELP ME!!!!!!!!!!!!!!!!!

PLEASE HELP ME!!!!!!!!!!!!!!!!!

Everything was running normally this morning. I was playing some game, then my computer froze, and showed this below.

"Intel UNDI, PXE-2.1 (build 083)
Copyright (C) 1997-2000 Intel Corporation

For Atheros PCIE Ethernet Controller v2.0.2.7(11/02/10)

Check cable connection!
PXE-M0F: Exiting Intel PXE ROM.
No bootable device -- insert boot disk and press any key"

My computer is acer aspire 5250 64bit

I *** need any help please. Does anyone know what happen on my computer and is able to ***ch me how to fix it?

(You don't have to type in English)