DedicatedSegmentSize value in registry doesn't do anything

[SSen0]

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 25.20.100.6444 . 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

2x4GB RAM

Intel HD 530

My Intel HD drivers are up to date. As of this post, it is on the version 27.20.100.8190 .

Thank you for reading and I look forward to a proper response.

Edit to add this-

Refer to this reply on this forums

https://forums.intel.com/s/question/0D70P0000068fInSAI

This explains the situation with GTA V and how changing the value in the registry affects it. This post explains it really well.

[Alberto_R_Intel]

SSen0, Thank you for posting in the Intel® Communities Support.

In reference to your question, just to let you know:

• VRAM is a special-purpose memory used by video adapters.
• VRAM is dynamic
• The VRAM cannot be increased because of a hardware limitation. 
• The video memory can get up to 50% from the system RAM, depending on the processor model and operating system
• Check the Maximum amount of graphics memory or video memory: https://www.intel.com/content/www/us/en/support/articles/000020962/graphics-drivers.html

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:

https://support.microsoft.com/

Any questions, please let me know.

Regards,

Albert R.

Intel Customer Support Technician

A Contingent Worker at Intel

[David_Mansilla]

Hi @SSen0, did you find a way to do again that vram setup? I'm having framerate issues with Warframe with an integrated Intel GPU and I would like to try what you talked about.

I'm sorry about posting in a thread almost two years old but I couldn't find a way to send SSen0 a private message.

[SSen0]

Hey @David_Mansilla, no I wasn't able to solve that problem with any of the newer drivers. The only solution was to install one of the old drivers and do the rest of the steps. I looked into the PC in question and I found the last driver I installed is 23.20.16.4901 and the registry trick is working fine. However, I haven't used this system for quite some time and I haven't tried the registry trick with any new drivers after making the original post, so you could try your luck there if you haven't yet. Good luck!

[David_Mansilla]

Thank you for the answer, @SSen0, I guess that, unless I find something else, my only choice is to try that registry thing with newer drivers, as the older driver you mentioned doesn't support the Intel iGPU's I own.

[n_scott_pearson]

There is no support for this registry entry in any of the DCH-based drivers. DCH drivers started with the 6444 build.

As for what is responsible, yes, it *is* the GTA V game's fault. They had no business using up the available VRAM for textures. That's just a bad design and a bad implementation. The fact that there was a workaround in the 'olden days' means nothing. This issue has been discussed before (ad nauseum) and the resolution was that Intel will not be supporting this workaround.

...S

[David_Mansilla]

I appreciate the answer, @n_scott_pearson, I guess then that I'll have to find other ways to improve perfomance in my laptop, but still, even if it didn't help in my case, I think it would be welcomed by all if Microsoft/Intel let the user set a VRAM value, just for the sake of customization, just like you have the ability to change the Page File size or let it be managed by Windows. Tecnically I can already, through BIOS, but only with 32/64/128 MB/auto values, but I'd like to set it to 1GB or 2GB and test the perfomance.

[n_scott_pearson]

What it comes down to is MS, as part of the DCH driver architecture, is pushing things like, not accessing the registry from drivers, not attaching control panels to context menus, using Modern GUI (a.k.a. Metro) apps for configuration, etc. Interestingly, Intel seems to be the only company that is following the rules MS put in place; AMD and NVIDIA seem to ignore them regularly.

...S

[drvink · Accepted solution]

I realize this is an old thread, but @n_scott_pearson is incorrect--this feature has not been removed from current (DCH) Intel gfx drivers. The location of the registry key has simply moved to meet Microsoft's "driver package isolation" requirements.

Anyway, the fix is easy:

1. Find the registry key for your Intel GPU. It will be one of the keys under "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}" (look for a ProviderName REG_SZ entry with "Intel Corporation" as the data, or other values mentioning Intel GPU driver files--if you have no other GPUs, then the key should simply be "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0001").
2. Add a new key called "GMM" under that key.
3. Add a new REG_DWORD value called "DedicatedSegmentSize" under the GMM key--its data is interpreted the same as in the old "HKLM\SOFTWARE\Intel\GMM" location.

Image attached to show it works.

 

[SSen0]

Thanks a lot for finding the solution @drvink . I don't have the old system anymore to use it, but I hope it helps other people who come across the same problem.

Tagging @David_Mansilla since he was looking for the solution last time.

[PlayerGab]

Interestingly, the new location of the key, provided by the Internet user on the Intel forum, that you mentioned, is wrong on my notebook by just one digit. Check it out:

Location cited here:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0001

Location on my Acer Aspire 5:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0000

Following the same steps previously mentioned by you, that is: 1. Placing the new GMM key in that place, 2. With the 32-bit DWORD value of 512, Hexadecimal base… interestingly, the system has now tripled the value I provided (instead of 512MB of dedicated memory, the VRAM registers 1536MB now). It wasn't what I expected, but it solved my problem. So thank you very much to all of you, guys.