I just upgraded my brand-new Inspiron 15 3525 Ryzen 7 5825u from 16GB to 64GB RAM with no problem. The BIOS recognized the new 64GB RAM immediately after boot. I just use my existing DDR4 32GB RAM module from OLO bought from AMZ. In addition, you can add one internal 2.5 hard drive to the 15 3525. There's a SATA cable and case for the 2.5 hard drive. I added my old SSD 840pro and it just works perfectly.
I would like to know how much RAM is supported by Inspiron 15 3525 Ryzen™ 7 5825U. Has anyone tried with 64 GB RAM? I am planning to purchase and upgrade to use for Cybersecurity Labs.   In Crucial, this model with Ryzen 5 support 64 GB (2x32GB).  Memory RAM & SSD Upgrades | dell | inspiron laptops/notebooks | Inspiron 15 (3525) Ryzen 5 | Crucial.com If Ryzen 5 support 64 GB, Ryzen 7 should also supports, but I am not expert on this. Any suggestion would be highly appreciated.
Inspiron 15 3525 Ryzen™ 7 5825U 64GB (2x32GB) RAM Support