@ernanibritto did you by any chance buy the crucial ram on aliexpress?

Crucial should work. And, if you buy from Crucial they guarantee compatibility or you can return the RAM. Here is Crucial's list of what is compatible for your laptop.

DDR5 RAM seems more finnicky that earlier types. Sometimes a seemingly-compatible stick won't play nicely with other RAM. So, if you are adding one 16 GB RAM module and you already have one 16 GB module installed, from another brand, it's possible that they may not work together. A matched pair is always the safest option, but adding a different brand may work if the frequency and timings are the same.

Follow the disassembly and reassembly steps in Dell's Service Manual.

Whenever touching components or working inside a computer, wear a grounded wrist strap, also called anti-static wrist strap, ESD wrist strap, or ground bracelet. It's a cheap and sensible precaution. Rest the laptop on an anti-static mat or at least a reasonable alternative such as corrugated cardboard.

Hello @lord_voldemortplease let me know if you have already tested this setup.
I'm curious about this compatibility, because I've already tested the corsair and, it didn't work. But, I discover that it's incompatible by the way because it has a different config as below:

DDR5-4800 • CL=40 • Non-ECC • SODIMM • 262-pins • 1.1V • 1Rx8 • PC5-38400

https://crucial.com/compatible-upgrade-for/dell/dell-g15-gaming-(5520)
https://www.kingston.com/br/memory/search/model/104645/dell-alienware-g15-5520

And remember the following instructions for the upgrade:

After you release the cover:
Remove the battery cable
Remove all the ram memory modules from the slots
push the power button for 15s
put the new modules on the slots
put the battery cable back again
Close the cover again
start the laptop by pushing the power button up for 30s
pay attention to the battery lights on the left side and, be patient ( it could take some minutes, take a break )
If the entire process work, the laptop could restart 3 times
If it's not, you will see the battery light indicator blinking 2 ambar and 5 white

And I'm looking forward to your answer,

My best,

Ernani

Hello,

Be carefull with Kingston this is a known brand that causes issues with Dell systems.

Beneficial information, and how's about crucial?

Hello,

Crucial allows you to send the memory sticks back in case it doesn't work so you can get a refund.

As I see on Ali express and Amazon, it sounds like that worked for some users. I'll try and see what happens.

I tested and it worked for me!

@ernanibritto​ Hi there! sorry to bother you, but I have the same laptop and recently upgraded from 1x8GB RAM to 2x16GB Crucial 4800MHz sticks. The laptop boots up fine, but after some time using it — even with lightweight programs — it randomly freezes and shows a black screen. I can’t do anything unless I force a shutdown. I don't know if anyone experienced this or knows what might be causing it? Any help would be really appreciated.

@loSMOKER​ Hey, I didn't. As I'm located in Brazil, I was concerned that I might be subjected to taxation. So I bought mine from an online store and got a good price at that time.