XPS 8940, cannot update BIOS 2.2.0, black screen

Hi DELL-Cares,

If you have solution you suppose open as public not private. I have on going Service Request for exactly same issue. The support engineer seems not aware about the issue that result they had me replaced motherboard. Of course result are same as not fixed issue. This seems disaster on DELL software quality control, failed on 2.2.0 then 2.3.0 keep same mistake. I really like to take 2.3.0 update since update addresses the Intel Security Advisory INTEL-SA-00562. But I don't want lost PCIe x 4 port.after update.

Happy Thanksgiving everyone! A bit of humor. That's what I've got from DELL-Cares:

Anyone have an idea how to do this without at least monitor and keyboard?

The person who wrote that message must have out scaled IQ or from alternate universe.

Yes, Chris. Of course, I knew, what to do. Just laughing. And btw, it didn't work. PCIe x 4 is still lost. Now, I'm waiting for reply from "Level-3 support team". "It would take 2-3 business days to hear from them".

It's a same problem, as a lot of people have with XPS 8940, BIOS versions after 2.1.3. And no matter what kind of PCIe adapter or SSD they're using.

Totally agree with you. I had asked them to provide status of producing the issue. The result is, yesterday they sent me similar email like yours "standard troubleshooting instruction". Without answering my request for status of producing the issue. I really wonder if they even tried to reproduce the issue. I will let you know if I get any updates.

After a month of talking about nothing, I see they even don't know what it's about at all. The most unprofessional team I've ever seen.

Two Three   Four questions from this dummy...

Maybe I missed it, but has anyone tried clearing BIOS after this update by removing the motherboard battery and pressing/holding power button on PC for ~30 sec (with adapter+SSD in x4 slot), then reinstalling the battery and seeing if it boots now?

If you installed a driver for the x4 PCI-e adapter, have you tried disabling Secure Boot in BIOS, save the change and seeing if it boots with adapter+SSD in the slot?

Has anyone removed the SSD from the adapter and tried to boot with an "empty" adapter in the x4 slot?

Is Windows Boot Manager still the 1st boot option in BIOS after the update?

EDITED

1. I've tried clearing BIOS by removing the motherboard battery and pressing/holding power button on PC for ~30 sec (with adapter+SSD in x4 slot), then reinstalling the battery (per your istruction) and it doesn't boot.
2. I didn't install any drivers. Secure Boot was disabled always. I didn't change it.
3. I've removed the SSD from the adapter and tried to boot with an "empty" adapter in the x4 slot and it boots as usual.
4. The Windows Boot Manager still the 1st boot option in BIOS after the update. And keep in mind, it hangs before you can get F2 BIOS Setup, or F12 One time boot menu.

Could it have been set to RAID when you installed Win 10 directly onto the SSD in the M.2 slot? AHCI is the default, but Dell typically ships PCs with it set to RAID.

If the power button blinks when it won't boot with the adapter in the x4 slot. count the blinks (and their color) because that's an error code.

And the power button isn't blinking. It's solid.

It hangs before OS start loading. I even can't go into BIOS setup with the adapter in the x4 slot.

I've removed SSD from x4 slot and checked the BIOS. It's still AHCI. The color is white. Everything as usual, except no more SSD in x4 slot.

AHCI. I didn’t change it.

@Vadimnj  After you reset BIOS by pulling the battery, is SATA Mode set to AHCI or RAID? (Don't change it.)