Problem with RAM upgrade on Precision 3660 Tower

Finally Dell won. I bought two modules from them.

Crucial promised a quick feedback from their internal team but I hear nothing...

Very disappointing this issue...

I haven't encounter memory incompatibility for almost 10 years. I bought the exact same Crucial memory and the machine won't past post even with only the Crucial memory (so it's not ecc vs not ecc). And of course Dell sells their memory with a 300% mark up (or 250% markup if you consider it does have ecc).

We have mostly moved with Lenovo for our new laptop and this is the only Dell machines we have ordered in quite awhile just to test it out. Guess I know what to choose in the future.

I (very) recently got a 3660 from B&H and sucessfully installed 64GB of PNY (4x16) MD16GSD54800. The first thing I did was -- on the Dell memory -- to fully update firmware (BIOS etc.) before changing the memory sticks. The PNY memory is significantly-- but not exorbitantly -- more expensive than the Crucial.

@RMW 

I hope you're right because I'm about to buy it for two 3660 workstations that I was very upset to find out the XPG RAM I bought didn't work in.

Worked for me: i7-12700, A2000 gpu, on last-to-current BIOS. No guarantees. If you have the money, buy Dell memory. I may have had beginner's blind-stupid luck...

FYI - before seeing this thread, I purchased Crucial 32gb ddr5 modules - none would work in the Precision 3660. (Note that Crucial now does not show any Crucial-brand compatible memory available for Precision 3660)

After seeing last posts in this thread, I purchased PNY 2 16gb PNY MD16GSD54800-TB and they work alone or together. I'll have 48gb system memory (2 PNY 16gb modules + the 2 original Dell-provided 8gb modules) - and I'll wait until memory prices deflate before replacing the 2 Dell 8gb's with 2 32gb modules. 

I also was going to try Atech 16gb module, which at the time was a bit less than PNY brand, but did not try.

Just a notice: If you're looking for compatible ram today on crucial website there is no compatible ram for 3660...

So they confirmed that there is an issue

Confirmed!

The PNY DIMMs from B&H worked on both my workstations.

Update from 15.11.2022

i checked with Kingston website, they say this RAM is supported by Dell Percision 3660 Tower

https://www.kingston.com/en/memory/search/model/104784/dell-alienware-precision-3660-tower

Specs.
32GB DDR5 4800MT/s Non-ECC Unbuffered DIMM

Part Number: KCP548UD8-32

DDR5 4800MT/s Non-ECC Unbuffered DIMM CL40 2RX8 1.1V 288-pin 16Gbit

as for Dell RAM, 

https://www.dell.com/de-de/shop/dell-arbeitsspeicher-upgrade-32gb-2rx8-ddr5-udimm-4800mhz/apd/ab883075/arbeitsspeicher#techspecs_section

as you seen, both RAMs has same technical aspects, so i am waiting for the Kingston RAM to arrive, we test them with our Dell Precision 3660 Tower, and i will keep you updated.

As for Dell technical support said that if the ram has the excat technical aspects, they will work regardless of the manufacturer.

I can confirm, Kingston ram works with dell 3660 Tower 

https://www.kingston.com/en/memory/search/model/104784/dell-alienware-precision-3660-tower

Anyone tried a model KCP548US8-16 ?

Another purchaser of Crucial Memory that didn't work.  I also purchased memory from Corsair that also didn't work.  In both cases, the system won't POST regardless of loading 1 stick or all 4.  I get the 2-amber, 5-white memory issue lights regardless of what I do.  Spec's wise, the memory should be compatible.
Trying the Kingston route now.. a pretty frustrating experience.  I'd just buy the memory from Dell if it wasn't more than 2X the price from everyone else.

You can try to get the same RAM part numbers from here as they are users validated. 

I've ordered this and will reply back here soon, but I can confirm that KCP548US6-8 DOES work, although POSTing takes much longer than the Dell RAM