That sounds like a hardware issue that is completely unrelated to Max. Yes, Max will use all of the RAM it has available if it needs it, but that's not a bug or defect in Max. Other programs will do the same thing.
Your issue sounds hardware-related. I'd pull the RAM out and then re-insert it, making sure it is seated perfectly. Then, I'd run some tests on it. Make sure the timings are correct for it in the BIOS and that it's not overclocked or some other BIOS setting is incorrect for the machine. You'll need to use your computer manufacturer's data, forum and documentation to do that.
Then, run tests on the RAM. Search the web for programs that fully test RAM for errors. There are a few free ones out there. This one is one of the oldest and best-known ( https://www.memtest86.com/ ). Once you get your machine tuned in and settled down, Max should run better.
You'll still have to watch your RAM usage though. If you see it run out, things really slow down and can get unstable. I have 128GB and I see my RAM usage creep up to 110GB all the time. However, doubling your RAM like you did will help you a lot. You just need to get your machine dialed in properly I think.
Rob Holmes

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3ds Max (2023-2026), V-Ray 7, Ryzen 9 9950X3D Processor, DDR5 128MB, Gigabyte Aorus X870E Master motherboard, Sabrent Rocket NVMe Gen5 M.2 drives, NVidia RTX 4090, Space Pilot Pro, Windows 11 Pro x64, Tri-Monitor, Cintiq 13HD, Windows 11 x64
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