The Web page linked to in the original post includes the following feature specification:
- Patented DualBIOS with Hybrid EFI technology for 3TB HDD support
The Hybrid EFI is a very buggy EFI implementation that's built as a layer atop a traditional BIOS. I've got a computer with this setup myself, and the firmware implementation is pretty awful. It is possible to boot it from a GPT disk, in both BIOS mode and in EFI mode (I've done so in both modes), although I've never tried it with a 3TB hard disk, so that may create some additional wrinkles. I'm not sure offhand what's causing your system to fail to boot; it could be any of dozens of problems, such as a missing boot loader, a misconfigured boot loader, or a BIOS bug.
One common requirement on some EFI-based systems booting from GPT disks in BIOS mode is to have an MBR partition marked as active. Since GPT includes a "protective MBR" with a single partition of type 0xEE, setting that partition active sometimes works around boot problems. You'll need to use an MBR-only tool, such as all but the very latest versions of Linux's
fdisk, to do this; or you can use a very recent version of
parted to set a flag on the disk as a whole. (I don't recall the flag's name, offhand, but it is
boot flag, which identifies an EFI System Partition (ESP).) OTOH, if you decide to try EFI-mode booting, you should probably not set this flag. If you try the flag first and then move on to EFI-mode booting, remove it before you go on to the EFI-mode booting.
Note that you could also convert your SSD to MBR form using
gdisk and leave your 3TB spinning disk as GPT. It's conceivable that this would help your computer work past whatever problems it's got. If you do this, you'll probably have to re-install your (BIOS mode) GRUB. Even Windows has no problems with systems that mix MBR and GPT disks, so long as the boot disk is in the right mode for the firmware.
The other approach is to try an EFI-mode boot. This is possible, but it's awkward on this board. One easy way to try it might be to download the CD-R or USB flash drive version of my rEFInd boot manager and prepare a suitable medium. When you boot from it, rEFInd should show you a set of boot options. If one of these boots into Linux, then you can try a disk-based installation. To do this, you'll need to shrink one of your partitions by ~550MiB and create an EFI System Partition (ESP) in that space. Mount that partition at
/boot/efi and install the Debian package of rEFInd. Unfortunately, one of the bugs of the Hybrid EFI is that it tends to forget its boot entries, so you might then want to type
sudo mvrefind.sh /boot/efi/EFI/refind /boot/efi/EFI/BOOT. This will rename rEFInd to boot using the EFI fallback filename, which will probably be more reliable on this board.
One more point: The downloads page for your board includes a "beta BIOS," which is probably a more reliable non-BIOS-based EFI. I can't promise it will work any better than whatever you've got now, but it might. (OTOH, if you're already running this "beta BIOS," it could be that returning to an earlier Hybrid EFI version would help fix your problem.)