View Single Post
  #2  
Old October 14th 14, 04:02 PM posted to alt.comp.periphs.mainboard.gigabyte
Paul
external usenet poster
 
Posts: 13,411
Default GA-78LMT-USB3 no BOOT USB

wrote:
Hi, I have a motherboard GA-78LMT-USB3 Rev 5.0 in which I noticed that the boot via USB storage is hassle-wrapped and wrapped by errors or does not work, since the USB ports are working perfectly, I guess it's a problem that concerns BIOS, no way to report it and hope it is fixed with an update?

Thank you so much for your attention.


On motherboards where the USB3 ports are supported by
an external chip, there is no guarantee that USB3 booting
is supported. This is consistent with how USB has worked
in the past.

I was lucky, on the recent motherboard I bought, that
the separate USB3 chip supports booting. The BIOS is UEFI,
which means it is a modern BIOS. A legacy BIOS makes it
less likely.

The only hardware with a reasonable chance of supporting
boot, is any hardware connected directly to the Southbridge.
They write good code for the Southbridge (your chip is SB710).
The USB2 ports and the SATA ports on the SB710 should
support boot.

Chips added outside the Southbridge, such as a VIA USB3 chip,
don't necessarily have Extended Int 0x13 support. It can be
added, but many chip companies do not have the skills to
add that code. Companies like AMI, Award, Phoenix (BIOS companies),
know how to write that code. Companies like VIA or NEC (some of the
USB3 chip makers), less so. Writing the code is complicated
by the need to support "emulation", so that the boot code
can support USB ZIP drives and USB floppy drives. It's not
easy to write a comprehensive boot support. Companies like AMI
and friends, they have done this before, so they know now
to do it, and test that it works.

http://en.wikipedia.org/wiki/INT_13H

Do not expect this capability to be added via a BIOS update.
Gigabyte is not wasting any development effort on a motherboard
originating in the year 2012. Development is finished. The
staff and engineers worry about the 2015 motherboards now.

Paul