ASRock 990FX Extreme9 + 1394 GUID are invalid

Great, glad to know that worked for you.

I wondered if a Firewire driver being installed would make a difference, which probably would not.

The Firewire/IEEE 1394 interface never became popular, even though it provided good performance, better than USB at the time.

I haven't seen a Firewire port on new mother board for a while now. Unless you buy an older external drive enclosure with a Firewire connection, you'll never need it.

Unless you plan on using an Intel 750 NVMe SSD, you don't need to update your BIOS version. There is a sticker on the BIOS chip that has the BIOS version number installed in the BIOS chip.

If you are not using a Firewire/IEEE 1394 device, then this message is nothing to worry about. The problem is hard to explain, and won't matter to you anyway. I have seen this issue a few times in this forum, for a few different mother boards. The fix for it might be a BIOS update. There is nothing wrong with your board, and you did not do anything wrong.

I understand it is inconvenient to press F1 every time the PC starts, so we will try to stop the message from appearing.

I said earlier to do a BIOS clear, but instead I think it will be better to do something else.

That is, I would suggest disabling the IEEE 1394/Firewire port.

To do that, you must go into the BIOS. If you don't know how to do that, there are a couple ways to do it.

The usual way is when you start or restart the PC, press the Del or F1 keys while the PC starts. That is, press the Del or F1 key before Windows begins to boot. You should press either key several times to be sure it is seen by the PC. That will put you into the BIOS user interface.

Or since you use Windows 10, you can use the ASRock Restart to UEFI ver:1.0.5 program. UEFI and BIOS are the same thing in general. You can download that program with the ASRock APP Shop program, if you have APP Shop installed. Or you can download and install Restart to UEFI from here:

http://www.asrock.com/mb/AMD/990FX%20Extreme9/?cat=Download&os=Win1064

You just install that program, and when ready, run it. You set both settings to On, and click Apply. The PC will restart, and then go into the BIOS interface.

Once you are in the BIOS interface, you go to the South Bridge Configuration screen. That screen has an option called Onboard IEEE 1394, that you can set to Disabled.

When that is done you then go to the Exit screen. You then click on the Save and Exit option, which will save your changes and restart the PC. Watch to see if that message appears again.

If you see the message again, then let us know and we'll see what else we can do.

Did you install any drivers for your board after you installed Windows 10?

Rodvik wrote: Just purchased an ASRock 990FX Extreme9 and getting the error below when I boot my computer up. "1394 GUID are invalid in both CMOS and Flash!" I'm running Windows 10. Current BIOS on the motherboard is P1.70 I have a Cooler Master 920 HAF Advanced Tower if that info is needed. Please help! Thanks!

Does the PC still boot when you get that message? Are you using the Firewire/1394 port with a device on that PC?

Did you try clearing the UEFI/BIOS to clear that message?

Your PC case information does not help.