How do I change Shared System Memory for GPU in Windows 11 without BIOS

Question

I have an Acer Laptop with following Graphics Configurations : Generic PNP Monitor and AMD Graphics Properties.

I had 4GB RAM installed and very recently have installed another 4GB. But the GPU is allocating 3GB shared system memory for itself. I want to reduce it to 1GB. I don't need so much VRAM as I don't do stuffs that requires GPU heavily, e.g. playing games.

I did some searching on YouTube and Google about this. Most answers are about changing in BIOS, which my laptop doesn't support(not available in BIOS options). But, there were other answers changing by RegEdit which is only for Dedicated Video Memory which I have enough. I want to reduce memory consumption by GPU from my RAM.

In summary, I am searching for an answer of reducing shared system memory in Windows 11 using Registry Editor and without BIOS, as I don't have the option in my laptop.

Answer 1

Because most integrated graphics solutions automatically adjust to use the amount of system RAM they need, for integrated graphics the Dedicated Video Memory value is completely fictitious. The system reports a dummy value simply so games see something when they check how much VRAM you have.

I don't know how you found 3GB as the size of the shared system memory, but this number is totally bogus. The video memory can only get up to 50% of the system RAM, and even that may be further limited by hardware considerations.

The amount VRAM your system reports can be modified in the registry. This doesn't actually change your VRAM - it just modifies that dummy value. You would typically increase it if a game refuses to start because you "don't have enough VRAM".

This registry item is found at HKEY LOCAL MACHINE/Intel/GMM as a DWORD called DedicatedSegmentSize, in units of megabyte.

It's possible that this value used to do some actual RAM allocation in older Windows systems (it's certainly documented as such), but in Windows 10 & 11 it's just cosmetics.