Cannot install operating system

I have a standard lenovo b570 laptop. I was tired of my operating system and wanted to install a new one. So to clear the hard drive I used dban and wiped it clean. Now when I turn on my computer with the installation cd in I get an error message. I don't know if I was supposed to do anything after running dban like install something, but there were no errors when dban was running. I did change the bios so that the cd would run first or the flash drive.
The error message says a bunch of stuff then:
pxe-e61: media test failure, check cable.
Pxe-m0f: exiting pxe rom.
This error occurs whether I try to install with cd or flash drive. So then I tried doing the same thing but this time I would have a Ethernet cord plugged into my computer it now said the same junk but instead of the pxe-e61 it said: client Mac addr: then numbers and stuff then guid: with more numbers and stuff
DHCP..... Then dhcp would disappear and this appeared: PXE-E53: no boot file name received
PXE-M0F: exiting pxe rom
If anyone knows what to do to get this computer running again please let me know ASAP