XPS 8940, find a fix or replace?

I was unlucky enough to go through the same problem you are going through. I tried EVERYTHING that was suggested here, to no avail. I ended up removing the graphics card and I haven't had an issue since.

@Y4L​ That's interesting. I will keep that in mind. Thanks.

Well, I finally had time today to do the clean windows install. We'll see how it goes now.

So I was on the phone with a Dell Support Agent, because I have TWO XPS 8940s also freezing (One AMD, One NVIDIA). I also am at my wits end. However, there is a new BIOS update, 2.19.1, that apparently addresses bug fixes. I installed it, and it still appears to be freezing for me, but worth a shot to install it on your machine.

@akess505, @LGordonG,

The ODDS on ANY BIOS alone fixing the Nvidia freeze/lock-ups are SLIM to NONE.

Seriously, depending on the problem, DDU can help (for Nvidia) but it is not a guarantee. There is probably no sure fire single answer for the Nvidia problem.

I've seen a myriad of answers here, and some claim to have had luck ONLY using the Dell POSTED drivers (usually not the most recent Nvidia versions though). Others say the non-Game Ready ones work OK. Other use a BIOS setting to turn off the Turbo Boost.

I on the other hand found a combination of BIOS version (V2.13.1, yes I am way back level) and the Nvidia Control Panel 3D power setting to Max. Power. I use the latest Nvidia Game Ready Driver, and do a CLEAN INSTALL on every new driver release (and check the Nvidia Control Panel to make sure it did not change the Power Setting, yes, it has done it occasionally). I install the new driver via GeForce when it finds a new driver.

Don't want to do any major tweaks or they do not work for you, disable the video card and use the on-board HD750 Intel video card built into the 8940... that will not cause a problem other than possible reduce display capability.

Me, until takes 'ownership' of the Nvidia problem and declares it fixed in the latest BIOS (problem started in Jan. 2021 with the release of BIOS V2.4.0) in the README for the new BIOS, I'll wait, or at least watch the forums if uses declared it fixed with the new BIOS.

So, I suggest at a minimum at this time, change the Nvidia Control Panel 3D Power setting and see if that helps?

@ispalteng ​ My 8940 is running 2.19.1 without issues, I did notice one thing with the new motherboard that Dell stuck in the system it is Pci Express 4.0, not Pci Express 3 on the GPU port. 

I realized this after dumping out all my old screenshots and PC pictures when I was tinkering with the 8940 a lot. My old board was PCI Express Gen 3 x16 on the GPU now it shows PCI Express Gen 4 16x though the Nvidia system info panel. 

I do know every board I had that was a dell board that ways GEN 3 PCI express had issues this does not. 

My XPS 8940 is running an RTX 4070, 64 GB DDR 4 3200 (2933) MHz memory, and the i7 11700. The only thing I changed was the cooler Noctua D12L in Dual Fan config. and the GPU. It was fine with the RTX 3060 ti as well after the MB change.  

I double-checked it with hw info, the replacement board is a Gen 4 chipset 

 Also, the motherboard through sys info is a Dell Inc. with Baseboard A00  I checked for anything on the motherboard that would say Foxconn or anything nothing, so it looks like an actual generic intel board customized for Dell. 

@JamieLinux​ 

One one of the thoughts and reasoning for the Max. Power as too many times the lock-ups occurred whenever the system was 'idle' and you moved the mouse, or were trying to wake it up from sleep. Thoughts immediately were the video card was 'sleeping' and somehow missed the 'wake-up call'. That or something overwrote the video buffer address (would not think that was possible). Tinkering with Max. Power, i.e., the card never reduced power or went to sleep.

Of course, each card IS different too, and some might not have that problem. Also, the DEFAULT 3D setting for power differs from card model to model. The Default being Adaptive power on my RTX2060. Others have Optimal I think or another default, but Max. power is no a default on any card.

Here is what the Control Panel says about my possible Power Settings:

So the assumption is/was if the card is always ON, that takes the card sleeping out of the equation.

I will say this, Dell and/or FoxConn or even Intel with the Management Engine changes that went to BIOS V2.4.0, none of them have either taken ownership of the problem(s) or even acknowledges it and/or appear to be working them.

If it works for you, great. I'm stable here, and until I know it is truly fixed without needing other tweaks, I guess I have to sit here.

I learned from BIOS V2.4.0 and later BIOS versions, in some case either you couldn't go back in version as the problem remained, or if it was working OK, the next BIOS broke it again.

I know I'm gambling with not going to the latest, and I will miss some Security fixes, but so far, that doesn't seem to be a problem (and I take back-ups twice a week).

My Motherboard is:

BaseBoard Manufacturer Dell Inc.
BaseBoard Product 0427JK
BaseBoard Version A00

According to the FAQ posted, these are the 'possible' 8940 motherboards:

Motherboards =
KV3RP Foxconn 02012PQ00-600-G, Released July 9, 2020
2W4W1 Foxconn 02012TA00-600-G, Released December 1, 2020, Brazil only
F1H92 Foxconn 02012YJ00-600-G, Released March 15, 2021, Brazil only
427JK Foxconn 02012VY00-600-G, Released March 15, 2021
K3CM7 Foxconn ??, Released July 14, 2021

The ?? on the last one sort of makes me think that it might not be Foxconn's? That was the one that Dell sent to be put into my 8940, and it would not boot? 2 of them even...

Possible there are newer or even 'beta' ones that Dell got/has? Don't know, but surprised they upped some components/chips?

I am quite sure you know how to determine the PCIe speed, and the 'standard' 8940 does not support 4.0. Of interest though is this link here, https://www.dell.com/community/en/conversations/xps-desktops/xps-8940-not-supporting-pcie-gen-4/647f94ddf4ccf8a8de7434a3 where this was discussed and explained to someone who thought they were at 4.0... (Spoiler, the card IS).

I can't see anything that points to me what speed mine is other than the 8940 Spec's per se. Mind sharing how you saw it? What Motherboard are you on? I'd be real angry if it is fixed in the motherboard though.

@ispalten​ You can install an old Nvidia driver it under system info tells you the PCI Express link if its PCI Express 3 it will say PCIE 3 x whatever link speed the card is. You can use HWINFO, or CPU-Z which will tell you the PCI Express link speed and version. 

CPUZ second tab mainboard Bus Spec

Honestly, I think they fixed the motherboard, that is all the info from CPU z which matches the system info.  I read that thread there I don't think I'm on the H470 chipset. I think this is more of a basic 490 or 590 intel chipset.

The Reason my current link speed reads 8gb is because that was taken with a 4060 ti 16 GB which is a PCIe 4 8x card. 

@JamieLinux​ 

Interesing....

Our 2 CPU-Z's next to each other:

So you have the newer motherboard my 8940 couldn't boot with I see. Also the latest BIOS from a few days ago.

It for me reports I have the H470 chipset. My card, an RTX2060 does have a Bus Interface of PCIe 3.0 x16 though. Motherboard though will not reach the max. capability it seems.

Wonder why on your motherboard it can't detect the Southbridge being used? We're both running the same CPU-Z version?

@ispalten​ That is because pci express 3.0 16x is the same as pci express 4 8x the difference in the reporting is I'm using a PCI e 8x card but I have a max link speed of PCI e 4.0 16 where you would just be capped at 8x PCI express 4 (because you are running PCI express 3.0 on the motherboard.

Your GPU is a PCI express 4x capable card but it's running link speed 3 so it caps at x16 3.0 speeds.  Hence why your link speed reports max supported 8.0 GT/s whereas mine says max supported 16x but running at 8x due to the installed GPU. 

As far as the Southbridge goes, I think because it's a Dell motherboard, not everything is exposed.  That is not uncommon. 

This is why I 100% think I no longer have the firmware to the driver crashing as Dell changed the motherboard to support a newer version which fixes the issues. I don't run with max pref on the GPU at all it works just fine.

as you pointed out in the other post, you have PCI Express 4.0 but the version of the motherboard you have does not allow for PCI Express 4.0 on the graphics pipeline.  Older H470 chipsets did not support PCI Express 4.0 for GPUs, later on, support was added for 4.0 GPU support. 

@JamieLinux​ 

I bit the bullet and went up in BIOS from V2.13.1 to V2.19.1.

I ran the Install EXE under Windows and checked the changes that were made/included going from V2.13.1 to V2.19.1. Some changes in the payload appeared to be minor:

There were some that did seem, like the IME's to have some 'larger' changes, but overall, not a large difference.

Of course, the 'hidden' part, the Security fixes and 'possible other fixes not documented'.

Hope it works OK for me. If not I hope I can GO BACK and be stable as I was before updating the BIOS.

@ispalten​ Good luck, to be honest, I think one of the issues with it, is the motherboards.  Some are Gen 3 boards; obviously, the newer boards are Gen 4 on everything.  The first board Dell Replaced it with was a Gen 4 board as well, but the tech hit the board with a screwdriver and killed one ram bank.  So I could only use 2 slots in single-channel mode. 

That got resolved I got the same board as the first replacement but with a better tech that was not so rough with components.