Inspiron 3668, memory upgrade

Promod117,

Below are the memory specs for the system.

Memory specifications

Slots Two U-DIMM slots
Type  Unbuffered dual-channel 2133 / 2400 MHz DDR4 SDRAM
•Supports 2GB, 4GB, 8GB and 16GB DIMMs, up to 16GB total
Speed 2133 MHz (Intel Celeron)
2400 MHz (Intel Pentium and Intel Core i3/i5/i7)
Configurations supported 2 GB, 4 GB, 6GB, 8 GB, 10 GB, 12 GB, and 16 GB

http://www.crucial.com/usa/en/compatible-upgrade-for/Dell/inspiron-3668

• Maximum Memory:16GB LOW DENSITY RAM
  
• Standard Memory:8GB removable
• Slots:2 (2 banks of 1)

http://www.crucial.com/usa/en/inspiron-3668/CT10043906

Specs: DDR4 2400 MT/s PC4-19200 • CL=17 • Dual Ranked • x8 based • Unbuffered • NON-ECC • DDR4-2400 • 1.2V •

Jesse,

Both sets of memory I tried met those specs. I have also tried the memory in a different board and they work correctly without a glitch. Is there some secret setting in the BIOS? I do have the latest version installed.  Here are the modules I tried.

GeIL GPR416GB2133C15DC

G.Skill F4-2400C15D-16GRR

Thanks,

Paul

7th Gen i5, as it came from Dell.....

Promod117,

What processor do you have installed in the computer? If you look at the specs in my above post it shows the type of memory needed for the Celeron Processor as well as Intel Processors.

Does this mean that no matter what brand the ram is, for at long as its only up to 16gb with 2400mhz, It will work?

My Inspiron 3668 is a success with 32 GB of memory. Additionally, it has confirmed that it is running on dual channels, using the latest BIOS 1.14.0. In order to confirm them, I use the latest CPU-Z v1.92.0 April 2020, the latest HWiNFO64 v6.28-4200 and so on. Of course, I know that multi channel support is not very significant in the current environment of Multi Core CPUs and Hyper Threading CPUs.

Now importantly, the Inspiron 3668 can have 32GB of memory. I've confirmed that many benchmark tests are about twice as good as when at 16GB.

If you suspect me, firstly you should read the explanation in CompuRAM web page.

By the way, I'm Japanese living in Japan and I am not an employee of CompuRAM and I live in Japan. So I was told that CompuRAM does not sell outside the EU and I don't have CompuRAM's products. 

Originally installed Micron Technology 16ATF2G64AXZ-2G3H1 in slot 1, I just plugged a UMAX UM-DDR4S-2400-16GB into slot 2.Of course, I do not like CompuRAM and UMAX. 

It's now UMAX that is the cheapest 16GB DDR4-2400 memory in Japan.

I would appreciate it if you could refer to what I have stated.

It would seem that Dell is a bit careless with the documentation as I have also upgraded my 3668 to 32 GB, using 2 different 16 GB sticks from Kingston. Mine came with a Kingston 16 GB KYXC0V-MIB (which I can't find a spec sheet for) and despite Kingston support also telling me the max is 16 GB, I bought a KVR24N17D8/16 and have had no problems so far.

Hi LHSBH,
I just purchased (2) of these Kingston 16 GB sticks (KVR24N17D8/16).... When these sticks arrive, is the installation as easy as removing the current sticks (the original 8 GB stick and the Crucial 8 GB stick that I added roughly 3-months ago when I thought the maximum was 16 GB), and turning on the computer to reboot? Or is there something I need to configure 'cause the RAM increased from 16 GB to 32 GB?

Thanks a bunch for your help.....

Dell Inspiron 3668, Windows 10 with a 64-bit operating system, x64-based processor

@LHSBH  - Just because the Specs say the max RAM is 16 GB, that doesn't mean 32 GB won't work. All it means is Dell hasn't validated this model to work with more than 16 GB. And that's why Kingston says the max is 16 GB.

And keep in mind this PC model was first released in 2016, when 16 GB RAM modules either weren't readily available and/or were just so expensive it wasn't worth the effort to validate >16 GB.

Hey Tomsey1,

My situation was slightly different in that mine came with a single 16 GB stick and I just added another but you should expect the same outcome - no config changes needed, the new RAM is automatically recognized.

@DELL-Jesse L 

"Below are the memory specs for the system.

Memory specifications

Slots Two U-DIMM slots
Type Unbuffered dual-channel 2133 / 2400 MHz DDR4 SDRAM
•Supports 2GB, 4GB, 8GB and 16GB DIMMs, up to 16GB total
Speed 2133 MHz (Intel Celeron)
2400 MHz (Intel Pentium and Intel Core i3/i5/i7)
Configurations supported 2 GB, 4 GB, 6GB, 8 GB, 10 GB, 12 GB, and 16 GB"

tl;dr  Mostly I want to know how resellers (even on Amazon) are selling 3880 Inspirions with advertised RAM configurations of 12GB when the documentation clearly states that such a configuration is not supported (or even possible...  ). Dell 3880 docs say only 4,8,16,32 or 64GB configs (matched pairs in multiples of 4GB, i.e. NO 1x4 + 1x8 pairings) - : https://www.dell.com/support/manuals/en-us/inspiron-3880-desktop/inspiron-3880-setup-and-specifications/Memory?guid=GUID-E9D2EA83-38A4-431D-803C-96D63C1DBC34&lang=en-us

background tl:

Hi JesseL, I am wondering something after seeing this.  Nephew just got an Inspirion 3880 - he says it is configured with 12GB RAM - and I just looked at the Dell spec-doc for the 3880, even specifically with the i5-10400 that his has.  The docs state that the two slots support 4 GB, 8 GB, 16 GB, and 32 GB.  Basically saying, as was always true in the past, pairs of slots must have matched DIMMs - and further, this 3880 does not support 2GB or 6GB, 10GB or 12GB - strictly 1x4, 2x4, 1x8, 2x8, 1x16 or 2x16.  In my experience the only way to get 12GB on was if the M/B had 4-slots, i.e. 2 pairs.. in which case you could do 2x4GB + 1x4GB, or 1x8 in the first pair, and 1x4 in the second slot-pair.. but never could you put a 4GB and an 8GB in to a single side, i.e. in to one pair.. and since the 3880 only has 2 slots... the 12GB configuration is simply not supported.

See doc at: https://www.dell.com/support/manuals/en-us/inspiron-3880-desktop/inspiron-3880-setup-and-specifications/Memory?guid=GUID-E9D2EA83-38A4-431D-803C-96D63C1DBC34&lang=en-us

I just really want to know if more recently the chipsets and/or MB have been modded to where they're not depending upon matched, sync'd memory/dimms in a two-slot mobo. ??   I see that the 3880 documentation - CURRENT documentation - says says that only matched DIMMs are supported - but how does it work with this 3668 I wonder?  Being a software-dev and ancient comp-sci master, I am certain that this would compromise performance of memory access (un-matched DIMMs) at the very least, and result in failure on many systems which explicitly require same size & speed of DIMM.

Apologies for the length - I really want to know if re-sellers are simply wantonly slapping un-matched dimms in to the 3880 without regard for the documentation or potential performance degradation (back in the early x86 days the system would recognize the pair at the LOWER of the two SIMM's specs (i.e. treat a faster 4gb chip as though it were a 2gb slower chip, just for example from 25+ years in the past, if one were to install a 2GB and a 4GB module in to a pair of slots).  Edit: Actually it was the frequency that was downgraded to the slower of the two module's speeds, and the slowest DIMM in the system determines the pace of the bus clock and memory access for all RAM.  Also - knowing that dual-channel mode requires matched DIMMs, these would default to single-channel async performance.  as far as I recall.

@aprilia8k  - Can't tell you what retailers may be doing, but the specs typically only list configs that Dell actually tested in a particular PC model.  That doesn't mean other configs won't work. And keep in mind that 1x 4GB + 1x 8 GB is likely to be cheaper than 2x 8 GB.

If you have mis-matched modules, RAM runs in "single-channel" mode which is slower and less efficient than "dual-channel" mode which requires a matched pair.

You can run CPU-Z (free) and click the Memory tab where it shows Channel # and will either say Single or Dual (mode).

You can run a 4gb stick with a 8gb stick. Some places will install matching ram even though they aren't the same size and will still work in dual channel more but the remainder of the 4gb's will run slower. I've seen 8gb with 16gb to make 24gb, not in 7th gen of course.