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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.

Ashraful Alam Shakil
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2 Answers2

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To start, I know this question is quite old, but in case someone stumbles upon it via Google:

Shared GPU memory is simply the memory a GPU can use if it runs out of dedicated GPU memory. On Windows, that value is 50% of the available RAM. However, keep in mind that "available memory" excludes memory reserved for hardware usage or integrated GPUs, so the value is often less than the total physical RAM.

For example, if you have a dedicated GPU with 16 GiB of VRAM and 32 GiB of available RAM, your GPU can use up to 16 GiB + (32 GiB / 2) = 32 GiB of memory. Exceeding the VRAM limit (in this case, 16 GiB) incurs a hefty performance penalty when shared memory is used, so it's usually not practical for gaming, though it may still be useful for other compute workloads.

Integrated graphics, on the other hand, reserve a small amount of RAM, typically 128, 256, or 512 MB, that is dedicated solely to the integrated GPU’s purposes. This is often why Task Manager shows a RAM value smaller than what you physically installed. Since integrated graphics have such limited dedicated memory, they rely heavily on shared GPU memory for anything beyond the simplest tasks.

It's important to note that shared GPU memory is not exclusively reserved for the GPU. As the name suggests, it's shared between the GPU and CPU, meaning it can be allocated as needed. Additionally, shared GPU memory is a limit, a maximum amount. It doesn’t mean that whenever a GPU exceeds its dedicated memory, it will automatically get the entire shared amount or nothing at all.

For most users, there's little to no reason to modify this shared memory value. If you're not running GPU-intensive tasks that require it, the shared memory won't be used by the GPU, nor will it be reserved, sitting unused just in case the GPU might need it.

Willi
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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.

harrymc
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