XPS 8950, future RAM upgrade

Makes sense to get them in pairs now instead of one stick.  I’m still thinking through my configuration, but whatever it is, I will make sure I get a pair now so I can put a pair in later.

Thanks.

Sounds like a good plan!

Have fun configuring your new PC and let us know what you order...

Here is the additional 16 gig parts that should work.  It appears Crucial doesn't have them in stock yet or the resellers.  Can save a nice chunk of change not getting the machine from Dell with 32 gigs.

https://www.crucial.com/memory/ddr5/ct2k8g48c40u5/ct21114900

If you're willing to wait, you could get this system with 2x 8 GB, assuming either config is offered, and get Crucial's 2x 16 when it's back in stock somewhere.

And if 2x 8 + 2x 16 GB doesn't work, you could always sell the 2x 8...

For what I do, 32 gig is honestly overkill.  16 is sufficient.  I just like buying future longevity a bit.  I will probably config now with 2x8 and then get the Crucial 2x8 when they come available or this summer.  Nothing I **need** right away.

I have a bigger deal that I have decided to roll into this I am working on ATM.  I have decided to get my parents an 8940, specifically the one from Costco that has the 11th gen i7 and 16 gigs without a dedicated GPU.  It supposedly comes with the 500 watt PSU and not the 360 watt, and also has Windows 11 Pro.  That’s a good thing since what has partly catalyst my interest is that I would like to upgrade to 11 but get Pro as a desire RDP and Bitlocker. Well, I don’t really want to fork out the non-transferrable OEM licensing fee on computers that are 3 and 4 years old to get rid of them in another year as I usually hold onto my desktops an average of 5 years before replacement.  

What that means is since my current 8930 I had configed with 16 gigs in 2018 when I got it (2x8) and then added 8 more gigs for a total of 24 gig (2x4), I am planning to take out the Dell-shipped 16 and put it in the 8940 to give it 32 gigs.  Then, I am thinking of swapping the blu ray drive in the 8930 with the standard DVD drive coming in the 8940.  The third leg is removing the RX 580 GPU which appears that I could get a very nice chunk of change for if I sold it considering the cost of GPUs right now and that is apparently a rather popular mid to lower level higher end card even for it’s age.  My other current two machines are Inspiron 3670s, one of which has a 1050 card that I can put in the forthcoming 8940.  Then, I can sell both Inspiron 3670s and the 8930.  This being a three way desktop replacement should be good for at least 5 years or longer.  Of the current machines I have, two have 8th gen Coffee Lake i5’s, the other a Coffee Lake i7.  Nothing I really **need** to do, but I figure before the current stuff I have gets any older and less desirable, now is the time to do it and I think I can maximize my savings by doing it now.

Ron:

I'm not sure your suggestion works. If I am looking at the specs correctly:

(https://dl.dell.com/content/manual29571812-xps-8940-setup-and-specifications.pdf?language=en-us&ps=true) page 15

Then Dell does not allow 4 sticks of 8G RAM to equal 32 total at all. I recently bought 2 sticks of 8G ram from Crucial to add to the existing 2 Kingston 8G sticks. My XPS8940 refused to boot. I get 2 blinking yellow, 4 blinking white led power lights.

Apparently the only 32G configs supported are a single 32G or 2 16G sticks.

To upgrade to 32G, Dell would have you throw away the existing 2 8G sticks, buy 2 16G sticks from them for $422. This represents a 50% price premium on the total computer cost. Unconscionable.

Please let me know if I'm missing something.

His suggestion is for an 8950.  I had posted most recently about doing what you said you are having issues with with an 8940, which is the same thing he said to also do with an 8950.  Check this other thread out.  It has been done a few people successfully, putting in 4, 8 gig sticks for 32 gigs on an 8940 even though it is not officially stated in the manual.  It has also worked with one 16 gig stick and 2, 8 gig sticks. 

https://www.dell.com/community/XPS-Desktops/XPS-8940-memory-upgrade-of-2x8GB/td-p/7779679/page/11

@Dell Doh  - You are missing something...

The RAM configs Dell lists in any of their Service Manuals are only the ones they validated for that specific PC model. Doesn't mean other configs, like 4x 8 GB, won't work but Dell didn't test it. 

Dell just isn't responsible if an unlisted RAM config doesn't work, but  chances are pretty good that an unlisted config will work. And as @srpawski mentioned, there are threads saying 4x 8GB works in the XPS 8940 even though that's not listed in the Service Manual.

Ron:

Thank you for the quick response. This made me go back & try for the 5th or 6th time and now it works with 32G. CPU-Z shows it running in dual mode.

Here's what I did differently: after unplugging the power cord, I held down the power switch for 15 seconds. Then I put the original 2 Kingston 8G sticks in DIMM1 & DIMM3 slots and the 2 Crucial 8G sticks in DIMM2 & DIMM4. While this is the opposite of what I previously understood was the proper way to do it (same brand is DIMM1 & DIMM2 - white color code and the other brand in DIMM3 & 4 - black color code).

After reboot, BIOS warning that memory config had changed. I confirmed and booted up properly.

Let me know if that makes sense to you!

On to solve this machine failing to go into sleep mode - I see you've responded to this issue as well.

@Dell Doh  By holding the power button, you reset BIOS which forced it to recognize the new RAM config.

XPS 8940 has a similar quirk with same solution: put mismatched RAM modules in slots with same color retention clips.  In the past, pairs of matched RAM modules had to be put in slots with same color clips for it to work. 

What speed is CPU-Z reporting for RAM installed the way you did?

Sleep:
There is a thread saying XPS 8940 won't go to sleep when the Dell OEM keyboard is connected. So try a different keyboard. Otherwise:

1.  Open a Command prompt window, run as administrator
2. Type in: powercfg -lastwake and press Enter
3. What does it report?

Hi Ron:

Here's CPU-Z result. Let me know if this seems reasonable.

As for powercfg, the result is:

Wake History Count - 0

I'm not using the Dell keyboard but instead a Microsoft USB wired keyboard and a Microsoft wireless laser mouse (attached via a usb wireless mouse receiver).

Thanks

@Dell Doh  = Your RAM is running at ~2933 MHz, dual channel, which is the upper limit for the XPS 8940. So that's good.

As for not going to sleep, did you look at the Power plan Advanced Options settings to make sure Sleep is enabled?

If your mouse has an on/off switch on it, try turning it off and see if PC goes to sleep now.  And check the Power Management tab for both your Ethernet and WiFi in Device Manager and uncheck the box to allow it to wake the PC, if the option is available.

Ron:

In Power Options Advanced Settings, Sleep Setting: 30 minutes

My mouse does not have an on/off switch. It's an MS Laser 6000 V1 - about 13 years old. When I unplug the usb receiver, the pc does go to sleep. But when plugging it back in, I can't get it to wake up again.

As for Power Management - I assume you mean Network adapters, Killer Ethernet & Wifi? I unchecked boxes on both but it made no difference.

If PC won't wake after you reconnect the mouse and click a button, does pressing any key on keyboard wake it?

Have you tried a different mouse to see if it also keeps PC from going to sleep and/or if reconnecting it will wake PC.

Open the Windows Power & Sleep screen. Click Additional Power Settings. On next screen identify the active Power plan and click Change Plan Settings. On next screen, click Change Advanced Power Settings.

On that last screen, disable Hibernation, Hybrid Sleep, USB Selective Suspend, and PCI Express Link State Management. Save the changes to the Power plan and reboot. See if that either lets PC go to sleep with this mouse connected and/or wakes up when you reconnect that mouse and click a button.