The memory should work unless you have a bad RAM module. Have you tried installing them one at a time. In other words try 1 and if it works pull it and try another just to confirm the integrity of each module? If that works then install 2  then pull them and try the other 2. Other than that it can only be incompatibility. Not that it matters but interesting that Crucial does not show 4 x 16 GB as a 64 GB kit. All they show is 2 x 32 GB which should not make a difference but Crucial may have found issues with 4 x 16 GB. That page is here.

I had the same issue with getting generic ram that should have met spec. I then used Crucial's compatibility checker (https://www.crucial.com/usa/en/compatible-upgrade-for/Dell/precision-7740). Got the specific SKU they listed and it was fine.

Hi,

sorry to revive old thread.

Just received my 7740 and using the crucial website I bought BL2K32G32C16S4B, which is 2x32GB 3200MHz. Laptop doesn't boot so thought it might need BIOS update, run that to the latest 1.8 (something, latest as of writing this post) and no luck.

Any ideas?

Thanks

Exactly the same problem here with Precision 7540 memory upgrade attempt with Crucial 3200MHz RAM. Doesn't boot. Updated BIOS to 1.9.0. Still doesn't boot. Crucial of no help. Call to Dell support was of no help. 100% compatible according to Crucial website. Seems to be 0% compatible. Have not seen a single mention of success upgrading 7540 or 7740 machines with Crucial (and Kingston for that matter) 3200MHz memory.

If I'm reading the new Setup and specification for 7740 correctly the restriction of how many 3200MHz modules can be used has been lifted..

Can someone confirm that 4x32GB 3200MHz will work, please? currently running 2x8GB 2666MHz + 2x32GB 3200MHz but looking to get all 4 x32GB 3200MHz

Thanks

I have a very similar question.

Can mixed sizes of dimm used to avoid needed to remove the harder to reach primary slots (under the keyboard)?

I would rather just add more to the back secondary slots.

Hi All,
My 7740 came with 4 * 8GB modules. After I replaced two of them with 2*32GB modules (HyperX, right specs (even faster) but not certified for this notebook) in the secondary memory location (on the back) I had the non booting issue as described here. putting in only one 32 GB module (leaving one slot free) did work (48 GB total memory). After I put the 2 * 32GB modules in the primary memory location (under keyboard) and putted the 2*8GB module in the secondary location, everything worked fine. Now running with 80GB! Hope this helps.

Hi, I have the same doubt.
I need buy this memory:
https://www.amazon.com/HyperX-Impact-3200MHz-Memory-HX432S20IBK2-64/dp/B08492TQGQ/ref=sr_1_5?dchild=1&keywords=ddr4%2Bram%2B64%2B3200mhz%2BSODIMM&qid=1620053804&sr=8-5&th=1

Is it the same one you bought?
Thanks.

Hi Hugo,

Sorry for the later reply.

Yes indeed that is the kit I ordered and still use without any issues.

kind regards 

Sander

I know it has been a while, but have you found an answer to your question?