My G75VX has had BIOS failure and I returned to the factory (bestbuy Geek Squad), they replace the whole motherboard.

Now the warranty has expired, but I found a issue with the motherboard or say BIOS, the on-board NIC has MAC address 11-22-33-44-55-66 and all my serial number info (uuid, sn, win8key) were missing.

And it seems I do not have CSM, secure boot options in BIOS as well, it used have these options and my G75VX is shipped with win
8. I just do a little research about, it seems the replaced motherboard is not labeled as pre-install win8 (http://rog.asus.com/forum/showthread.php?36766-Missing-Fast-Boot-CSM-amp-Secure-Boot-Options-in-Bios...), thus it does not have these options.

Anyone have any idea about how to get these option back?

Thank you!

PS: I found a tool (called bt.exe using in DOS) to mod asus bios info, and I add my MAC address back (because I lost the original MAC, thus I have to override it with one of my old wireless card MAC which is not used any more). I find the offset of MAC in bios, but I have no idea about where asus label OS information.