Lenovo z51-70 Secure Boot option is not visible under Security menu - unable to boot from DVD.

[Stalq]

Hi All,
I've just got my brand new Z51-70 without OS (because it is cheaper) and wanted to make a clean install from my CD containing Win7. To my surprise I couldn't find in the BIOS option to boot from CD. Googled for a while and found that I need to set the Boot mode to Legacy Support and Boot priority to Legacy first. Then a bit down on the screen I adjusted the order so the ODD-DVD drive apears before HDD. This did not help. Googled again and found that I need also to disable Secure boot option under Security menu in the Bios. The problem is that there is no such option available ! And now I am stucked for good. Can somebody help me ?
Thanks,
Rafal

 

[popatim]

Power up watching the bottom of the screen
Press the F-key that corresponds to 'select boot media' (you might need to reboot a couple times to press the right key in time)
- For a UEFI install (graphical Bios), select the flash drive option that begins with UEFI:
Install should begin normally now.

*You may need to click "Drive Options" on the "Where do you want to install to" and then delete existing partitions. Install doesn't like to show drives that it thinks have an OS on it already.