First let me start by saying that this used to work one time but now don't. The exact last driver version with which this worked is 18.104.22.16844 . Any driver before then worked too. So, as you can see that driver is pretty damn old. It was released late 2018. And after then, the problem I bring up here is a problem for more than 1 and a half year.
Anyway back to the problem. In the registry, using the path HKEY LOCAL MACHINE/Intel/GMM, you could make a new DWORD called DedicatedSegmentSize. The value of this is showed as the dedicated video memory in display adapter properties. Like I said, this used to work perfectly. I have put values of 2048 MB and it would work. Basically it would allocate that memory always to the IGPU.
Now, I know that messing with the registry is not recommended, but listen to me. I will give an example why you need this trick to play some games.
GTA V is one. When you dont have this trick enabled, GTA V shows the total video memory in its in game settings. And it gives rise to a number of problems. The game is notorious for caching textures. Since it assumes you have 4GB of VRAM (I have 8GB of ram, so total video memory is 4GB), it uses all of it to cache textures. This only leaves 4GB for Windows and the game itself and it leads to stutters every second, making the game unplayable. The game starts out fine. You can play it fine for the first few minutes. Once you start driving around and the textures start getting cached, it stutters. It literally freezes every half a second but it still works. Anyway, its unplayable in this state.
Now before you state that its the game's fault, no it isn't. If you set the dedicated video memory to 2GB using the DedicatedSegmentSize trick, the game then recognizes that you only have 2GB of VRAM. And so it caches 2GB of textures rather than 4GB, and this leaves 6GB for Windows and the game itself. In this state the game is perfectly playable. It runs at 720p at 30fps with very high textures and other setting on lowest. Trust me, I have played the game for more than 100 hours using this trick.
I bring this up now because I have recently taken an interest in GTA V again. I just want to know why this harmless setting was removed. Why was this trick disabled? It does nothing now, no matter what value you put in the registry. Is there any other way to change the dedicated video memory in the registry that was added instead? Please I need to know. Is it possible to bring this back by any chance? And if there is any other possible way to change dedicated video memory, I would like to know. I know you can do something like that from the BIOS too. But trust me, I tried everything. Literally everything. I spent a whole day trying to find a way, but there isn't any. So, may I ask again, why was this seemingly harmless setting in the registry removed?
I will my PC's specifications below-
Gigabyte B250M D2V
Intel Core i3-6100
Intel HD 530
My Intel HD drivers are up to date. As of this post, it is on the version 22.214.171.12490 .
Thank you for reading and I look forward to a proper response.
Edit to add this-
Refer to this reply on this forums
This explains the situation with GTA V and how changing the value in the registry affects it. This post explains it really well.
SSen0, Thank you for posting in the Intel® Communities Support.
In reference to your question, just to let you know:
As you mentioned previously, it is not recommended to access the "Registry" since depending on the changes done in there it might create instability on the system, some features and functions might not working properly if the wrong changes were done.
So, if you are interested in knowing "why was this trick disabled?" or any other question about the DedicatedSegmentSize, the best thing to do will be to get in contact with Microsoft directly for them to provide further technical assistance on this subject:
Any questions, please let me know.
Intel Customer Support Technician
A Contingent Worker at Intel