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XPS 8940 SE, third party RAM cannot run at 2933MHz
PS 8940 Special Edition, Intel i7 10700K, came with 16GB RAM 3200, runs at 2933.
I am trying to upgrade to 64GB ram. tried 3 popular brands, none of them can run at 2933 or 3200.
- Corsair Vengeance LPX 2x 32GB, DDR4 3200, can only run at 2133
- Crucial Ballistix 3200 MHz DDR4 2x32 GB, can only run at 2400
- HyperX predator 3200 2x32GB, can only run at 2400.
All these third party RAMs requries to turn on XMP in the BIOS. But Dell's BIOS does not have such options.
Dell's original parts are so expensive,1 x 32 GB cost 361.9$. Third party RAM 2 x 32GB cost ~ 280$. And third party rams come with the fancy RGBs and heat sinks.
Anybody has luck to get third party ram work at 2933MHz?
Fei Crane
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November 6th, 2020 17:00
In summary, I got two different 1.2V memory models work at 2933 in XPS 8940:
- Crucial CT32G4DFD832A.16FB1
Amazon marked it as single rank, but it is actually dual rank.
The part number is very very close to the Dell origin parts. Dell shipped with low end crucial memories, and sell them at more than double the market price.
- Mushkin MSL4U320NF32GX2
Amazon has a bunch of them, different models, but not too much difference (with or without heat sink), any of them should work.
Both works fine with the 2 * 32GB, and/or together with the original 16GB come with the XPS computer. Both are CL22. Both are pretty cheap.
The other popular gaming RAMS on the market at 1.35V + can worker too, but won't run at 2933, can only run at 2400.
DELL-Cares
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November 3rd, 2020 14:00
Thank you! We have received the required details. We will work towards a resolution. In the meantime, you may also receive assistance or suggestions from the community members.
Vic384
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November 3rd, 2020 16:00
Was the Crucial Ballistix RAM one of the compatible upgrades listed here: https://www.crucial.com/compatible-upgrade-for/dell/xps-8940
Fei Crane
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November 4th, 2020 00:00
Yes, I chose the Crucial model from that compatibility list. Apparently, they didn't test it out themselves. So don't be misled by that list.
I contacted their technical support by email. Their support is not technical at all. They simply forwad some links in their website, which is not related with my issue at all. Seems the technical people respond to email once per day after breakfast.
I submitted a survey and rated their technical 0 start. Then later, a product manager contacted me, asked me to "turn on something called XMPin the BIOS", "I downloaded the user manual, but unfortunately I don't see XMP as an option, you need to contact the computer manufacturer ...."
Come on, I clearly explained Dell's motherboard have no XMP option in my very first email. Not only XPS 8940, I never heard of any Dell motherboard has XMP option.
So far, never heard back again from Crucial.
Vic384
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November 4th, 2020 06:00
@Fei Crane I am beginning to think that this is a problem with the XPS 8940. Since the XPS does not use the XMP, it depends upon the SPD information. It may be that the memory you have tried does not have the information required to set the speed at 2933 MHz. If you look up the specs of the Corsair Vengeance memory you used you would see that the SPD is 2133 MHz which is exactly the speed you got. The HyperX memory specs do not list the SPD and usually, with Crucial memory, the speed rating is the SPD although it too is not listed in the specs. With most memory manufacturers if they indicate a speed it is the tested speed using the XMP.
speedstep
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November 4th, 2020 06:00
Ram speed is determined by FSB of the cpu and XMP profiles etc.
You cant mix speed and vendor and profile and expect it to work correctly
Adding faster ram does not change the Profile for a given processor.
Along with speed ratings, RAM also has ratings for timing.
This appears as a string of numbers such as 9-9-9-24.
SPD stands for Serial Presence Detect, meaning that the motherboard expects the RAM to correspond to one of the JEDEC profiles or XMP Profiles. You cannot mix speed and profiles and vendors with good results.
Ram speed is mostly marketing. You are falling victim to the MHZ Myth.
https://www.youtube.com/watch?v=D_Yt4vSZKVk
Fei Crane
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November 4th, 2020 10:00
Of course it is Dell's mother board issue. From the information I got so far, Dell's mother board cannot provide enough power to 1.35V Rams. 1.2V Ram would work fine. I am in the middle of testing out.
What I don't like Crucial is: their website claims the ram is compatible with XPS 8940, but it is not. And their technical support is not professional at all.
Overall, feel XPS is a shabby computer. I hesitated to DIY a computer by myself, or by a existing one. Haven't DIY computers for years, now found out everything is RGB, and turning off RGB is a hassle, so finally just bought one to make it simple. I know Dell won't use the best parts, but still disappointed by what I got.
Fei Crane
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November 4th, 2020 11:00
I have watched that specific Linus video and other videos before. I still want to my ram run at 2933 instead of 2400. I don't call that a "failing victim"
Vic384
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November 4th, 2020 13:00
I am not aware that you can set the RAM voltage in the BIOS on the XPS 8940 motherboard although I am pretty sure the issue is not that there is not enough power to supply another 0.15V. Perhaps you should have brought memory that is rated with an SPD of 3200 MHz at an SPD voltage of 1.2V While the SPD specs of the Crucial Ballistix memory are not listed the voltage listed is 1.35V. Perhaps you should have purchased Crucial 64GB kit DDR4-3200 (CT2K32G4DFD832A) which has a rated voltage of 1.2V. For the Corsair memory you tried, the SPD speed is 2133 MHz and the SPD voltage is 1.2V.
I am not why you are critical of Crucial and not Corsair. Crucial's memory worked but not at the speed you wanted just like Corsair's memory. Crucial's issue may be the rated voltage and Corsair's issue is that the rated speed is different than the SPD speed.
speedstep
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November 4th, 2020 16:00
Fei Crane
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November 5th, 2020 00:00
No I am not convinced MHZ = performance.
Yes I understand the memory speed is not the most important one.
And yet, I still want to reach 2933 HZ.
You can treat me as ADHD. I just want to resolve this issue.
Thanks for your response. But please stop concluding what I am thinking.
Please stop convincing me that I don't need to do this or that. I know what I want. I got my CS master degree. I have worked as software engineers for >10 years. I have worked on products that requires to fine tuning every system call, context switching, high IRQ rate, DMA, microsecond level resolution timers, jiffies. I have worked in almost every CPU architect. I know the system in and out. I have DIY PCs for myself and my friends before. I did enough research on the RAM brands in the market.
I have bought some 1.2V RAM, the 1.2V RAM runs at 2933 perfectly in XPS 8940. And they are pretty cheap. My problem has resolved.
Thanks all for the input.
Vic384
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November 5th, 2020 04:00
@Fei Crane I order to help others that may have this problem you should post what RAM (manufacturer and model #) worked for you. Also, you should mark this post as having a solution.
Fei Crane
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November 5th, 2020 09:00
I am still waiting on another brand of ram.
Will summarize once I test that out.
Vic384
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November 16th, 2020 12:00
@KGA4841 To run in dual-channel mode memory modules need to be install in slots with similar colored securing tabs. So if you first memory module is in slot 1 (DIMM1, white) , the second memory module should be installed in slot 2 (DIMM2, white).
KGA4841
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November 16th, 2020 12:00
@Fei Crane
Sorry if this is newb question but if I were to add a 2nd memory module (the first being the one that shipped with pc) and I wanted to add a 2nd of equal specs (ie. one of the two models you mentioned) which two DIMM slots are used to allow for full dual channel compatibility?
factory memory is in slot 1-white
i asked some others about this and got different answers from each:
- one told me 2nd memory module goes in slot 2-white
-another said slot 3-black
-and yet another even said slots 2+4 white/black to allow for running in dual channel mode