On power up the DEL key will get you into the BIOS which has an American Megatrends Inc copyright message. At the top of the screen it's identified as the Aptio Setup Utility with a 2013 copyright. The 'Main' screen identifies it as BIOS version t680M v1.51 dated 02/26/2018.
Under the Advanced tab is an entry for CSM Configuration. This is the Compatibility Support Module Configuration and is where you setup UEFI and/or Legacy booting.
Elsewhere the Boot tab lets you setup the order of booting.
I noticed a slight oddity on the Advanced BIOS screen. Under 'Miscellaneous Configuration' there is a single item labelled 'OS Selection' which can be set to 'Windows 7' or 'Windows 8.X'. My t68 came running 'Windows 10 Enterprise 2016 LTSB'.
On power-up, if you wish to override the default booting behaviour, hitting the F7 key brings up a boot menu. (If an administrator password is set you have to enter that first). On my system with a Sandisk Cruzer Blade USB pen drive plugged in I got:
Please Select Boot DeviceRealtek PXE B01 D00 SanDisk Cruzer Blade 1.26 UEFI: SanDisk Cruzer Blade 1.26 UEFI: Built-in EFI Shell Windows Boot Manager (PO: mSATA mini 3ME4) PO: mSATA mini 3ME4 Enter Setup↑ and ↓ to move selection
ENTER to select boot device
ESC to boot using defaults
The exact menu you get will depend on what you have plugged into the USB port(s) and what you have set the boot mode to. (UEFI/Legacy/both).
You use the up/down arrow keys to select a particular entry and then hit Enter to boot it.
Alternatively the ESC key brings up a different menu headed Atrust Thin Client Menu
Normal Boot Reset Mode Firmware Update Reboot Shutdown
According to the manual
Normal Boot | Powers up your t68W as the normal startup procedure |
Reset Mode | Resets Atrust Client Setup settings and remote management status for your t68W |
Firmware Update | Updates firmware for your t68W through the network. |
Reboot | Restarts your t68W |
Shutdown | Powers off your t68W |
However fitting a new (and empty) mSATA flash drive showed this menu to be part of the Atrust OS environment, not part of the BIOS.
My t68 came with no BIOS password set. At the time of writing I do not know if Atrust have a default password for the t68.