This is just too funny. All along we have been concerned about "Secure Boot" and not being able to remove it. In one of the first UEFI documents I saw it said the Signature Store needed to be erased then we were told we had to set the BIOS password and then we could disable "Secure Boot". OK
Then I noticed that it still would not allow non-UEFI boots and the Secure Boot functions under Security could not be changed. After trying just about everything I figured I might as well enable "Secure Boot". Surprise, once I enabled secure boot, the security options, ERASE and RESTORE, became selectable.
I would appreciate confimation from Acer Technical before suggesting that anyone try this since it might brick but it looks like to disable UEFI in a W510.
1) enter BIOS setup
2) enable BIOS password
3) Enable F12 boot
3) In INFORMATION, erase the secure boot settings (will probably ask for confirmation)
4) In BOOT, disable Secure Boot.
5) Reboot and use F12 to enter boot selection.
Note: To use the Acer recovery, UEFI must be enabled (this may be what the "Restore Secure Boot" selection is about)
Again, do not try this (I have not) unless you really understand the risks. Acer please confirm, deny, or point to an updated document for UEFI and the W510.
ps if you have seen my other posts, while the Clover Trail sytem looks like it could support other OSs, Intel specifically said "not Linux" & only Windows 8 has the power management and thermal controls the W510 needs (sealed case, no fan). Anything else risks overstressing something. If you cannot do what you need to with Windows 8 you may need a different tablet.
Now is this just could have been said up front...