Use the one in the tutorial, that one worked for me.
Made a bootable usd with the cent os iso nd the program in the guide.
Will try to boot it up now... the usb is also 8gb so should be enuff space...
Edit: Still the same result...
Boot failed, no root device found
Sleep forever
Dont know what to do now...
Edit 2:
Cant get it to work, will just run with win7

What brand mobo you using? If it's Gigabyte, they are infamous for having random sudden problems booting from USB ...
hey Viceroy, +1 for this guide; I burnt my CentOS 6 iso to cd just now and am going to give it a go after next payout