XPS 8940, power down issue

@Ken No Be​ 

I assume you know about all the locking up on XPS8940's with Nvidia cards and the myriad of 'fixes', some that work for some, others that work for others? More Nvidia Control Panel settings vs. the Nvidia card/driver, or some BIOS settings collectively.

Since your boot drive is an SSD, Hibernate is not suggested or required. Normal 'sleep' options are better.

I also think you probably have SOME USB devices that are allowing the PC to TURN THEN OFF to save power, really not needed for a desktop.

Offered at Costco? The XPS8940 is 'old', from 2021... Seems odd they sell old or reconditioned PC's?

By the way, what BIOS version were you having problems with?

Note the PRIOR last post here was from Nov. 2023, I would suggest you start a NEW SUBJECT on this as well with complete details of you PC and exact problem and what if anything you tried? You POWER BUTTON setting would help too.  There is no option for it to wake from sleep, so what you see is normal, it powers on.

I assume you've only had the XPS for a short time as well?

Odd behavior that when I tell it to shut down from Windows, it would appear to do it.  But when I restart with the power button, it would be active for a second or so then "shutdown" again.  Then I push the power button again it would start with the Dell logo.  
Kinda does the same with hibernate function, everything saved then lights out.  I can tell from my UPS that it's "OFF".  Does it's false start for a second or so then shut off again.  Power button again and it will load to the pre hibernate state with everything that was running at the time.
I have also used sleep which draws some power to keep things running in memory, touching a keyboard or mouse wakes it up right away, no problem there.  I just don't use it if I'm away for the rest of the day and there's an extended power outage or something.  (I have it on a 1000VA AVR UPS.)

Next issue is adding a graphic card.  Picked the GEForce RTX 4060 8 GB OC 3 fan card for its lower power consumption and work with the 500 W OEM PSU.   

.  Will not "drop in" as the front and back lips on the case sticks out so you have to push the back lip apart to allow the card to angle in with the ear tab first then force the front lip out for the front corner of the card to drop down. The card was not recognized on power up.  The front corner of the card PCIe fingers were not down all the way.  The DELL case area where the full size graphic  sits in was tapered in toward the bottom of the case so was wedging the card out of the slot.  Got a metal punch and squared out the taper and the card will now fully seat and lock on the motherboard.   Next is the OEM graphic card lock down bracket will not click back in even with the rubber hold down piece removed to maximize the clearance.  It just 2-3 mm too thick and the case will not slide closed. Removed bracket and check the motherboard connection is secured and locked and buttoned it back up.

Graphic car recognized.  Download and install latest Nvidia driver and app.  Reboot and ran Furmark test.  It cranked along maxing out power on UPS at 250 W or so.  Programs that can use GPU start attaching themselves to it.  

Then the lock up started in idle state.  Nothing was running and power was minimal draw.  It was not starting sleep or screen saver, the browser was displaying whatever site but keyboard and mouse froze.   It never went to sleep so had to do a hard power off.  Intermittent lock up twice a day with no rhyme or reason.

Ran Dell update and everything installed except for the Bios.  With the weird shutdown/restart, it never updated after going through the motion.  Never did see the bios  progress load as shown on the tutorials. 
Tried the manual load and it seems to hang the shutdown and silly me push the power button and it would does the 2 second shutdown before it will restart with the next power button push.  Bios did not update.

After several retries, decided to wait it out and let it be and go eat dinner while it's mulling the shutdown.  Came back and it rebooted into Windows.  Checked and the Bios is updated, yay.
BIOS Version/Date Dell Inc. 2.25.0, 12/9/2024

Anyway, the weird lockup still occured while idling.  All internal tests have been ran and the Furmark still cranking for half an hour with no problem.  Just crazy that you turn around to get a cup of coffee then have to reboot and lose whatever you're doing when you get back.  Tried all the registry check/restor/sfc commands.  Memory checks OK.  Weird.

Sent the card back for refund.  Back to barebone config and no lock up for now. 

Try changing the BIOS AC Recovery option for what to do when recovering from a power failure from Off to Boot....