Gene said:
Now *that* amazes me! USB 3 should be totally backwards compatible with
USB 2...
But in the face of concrete evidence, I can't argue
That also makes my remarks above about hubs moot.
I'm glad you solved it!
The BIOS treats USB ports differently. It all depends on
where they're terminated in hardware.
CPU
|
NB
|
SB ------- Add-on Chip (NEC, Asmedia, Etron etc)
| |
USB USB3
Ports
The BIOS typically has "full" code, for the vertical column
of stuff. That code is written by the likes of AMI/Award/Phoenix.
The motherboard companies don't write as much code as you'd think.
They buy it, as a package for the chipset.
The Add-on chip, could have a BIOS code module, but it might
not have complete functionality. That leaves in question,
whether the BIOS can boot from an add-on USB3 port, or
work a HID device (mouse/keyboard) at BIOS level. Or
for that matter, listen to the wireless dongle of your
HID devices.
Once the OS is booted, the treatment of the ports, is as good
as the built-in OS driver can do. Or can be augmented with
a separate driver. WinXP might not know what to do with an
add-on USB3 chip for example, and need a separate USB3 driver.
There are a few chipsets (AMD A75, Intel Z77), where the USB3
is on the Southbridge (SB). In which case, AMI/Award/Phoenix
would include some kind of code for the built-in ports.
So understanding what happened, is easier if you know whether
the port in question, is off SB, or is coming from a separate
chip. The vast majority of boards to date, would have used
an add-on chip like the NEC. Integrated ports aren't all that
common, due to the late ship of USB3 on motherboard chipsets.
The add-on chips had a large head start.
Paul
