The RBT-820 has an XpressROM BIOS. Hit the F1 key on power-up to enter the setup screens. In my sample of the RBT-820 hardware I found I had three variants of the BIOS:
Version: 168LX_1.03.05 Built: 09/29/2006 13:44:59
Version: 168LX_1.03.06 Built: 10/24/2006 10:22:38
Version: 168LX_1.03.07 Built: 09/14/2007 13:40:28
Visually there was no difference between them.
The Main Menu is shown below:
There is quite a lot you can fiddle with in the BIOS should you want to.
As far as the 'Boot Order' screen, this is shown below.
I had no problem booting Tiny Core 8.0 from a pen drive.