Toshiba satellite L355-S7812

Hello,
My sister has a Toshiba satellite L355-S7812 model PSLD0U-00800X.
I thought she had a virus. tried to restart system from disks. failed.
Called toshiba they said it was a bad HD because of the screen message no bootable disk.
I purchased a new HD WstrnDigital - WD3200BEVT - Compatible
Western Digital WD3200BEVT - Hard Drive - 320 GB - internal - 2.5 inch - SATA - 5400 rpm - buffer: 8 MB - FOR SATA LAPTOPS ONLY
Still will not work.
screen says:Intel undi, pxe-2.1(build082) copyright(c)1997-2000 intel corp for realtek RTL 8101E/8102E pc1-E Ethernet Cont V105 (071227)
PXE-E6: medea test failure, check cable
RXE-MOF Exiting PXE Rom.
No bootable device-insert boot sickand press any key.

Please help I feel like I broke my sisters computer when all I wanted to do is help.