I am trying to install CentOS server on a machine that also runs Windows 7.  Towards this end:  1.) I created a 100GB Unallocated partition using the Disk Management tool in windows 7.  2.) I then downloaded Universal USB Installer from this link http://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/3.) I used the installer to creat a USB stick with the CentOS iso file.4.) I turned off my computer5.) Inserted the USB stick into the usb drive6.) Then started the computer.  But Windows launched instead of giving me a prompt to install Linux.  I know the computer read the usb drive because the light on the usb drive went on before windows launched.  What am I missing? 
linux boot stick being ignored on windows 7
linux;centos;windows;dual boot
Use This tool Instead: LinuxLiveCreator.  I've Found it to be more reliable.  After doing so, reboot.  If you still receive Windows7, you need to change the boot order in your BIOS to include USB devices.