How can this be explained? (shared video mem)

[thecrafter]

As you can see from the picture below, I have 3GB RAM installed. 64 (or 358, a little confused) is supposed to be shared/taken by the integrated GPU.

Yet that's not the case? As you can see aside from some random 26MB as reported, everything else is available. How can this be?

 

[Mr34727]

What does the BIOS setting say is allotted? On the x3100, you should also be able to change allotment in the Intel tray icon

 

[thecrafter]

What does the BIOS setting say is allotted? On the x3100, you should also be able to change allotment in the Intel tray icon

Doesn't really matter. The point is Windows is reporting that the GPU isn't using/sharing any RAM at all, which cannot be as this chip doesn't have GPU RAM of it's own

 

[Forceman]

Is it included in the "In Use" portion?

 

[rhansen5_99]

If I recall correctly the 3100 chipset can dynamically allocate memory unless you specify specifically the amount you want in the bios.

 

[thecrafter]

Is it included in the "In Use" portion?

Ah great point!
/feels stupid

 

[omegatotal]

actually the 'hardware reserved' is including the amount for required basic rendering of your windows desktop at that screen resolution and color depth, once you launch a 3d application (say google earth in opengl mode) that should change, otherwise it is including it in the 'in use' group in that resource monitor

 

[Telo]

If you look at the GPU screen, it tells you the following:

1] That it has a built in 64MB of RAM [you can scan your MB and you will see some RAM chips around the GPU].
2] You have assigned 0MB of dedicated RAM [RAM that it will already have assigned to it].
3] It will use up a max of 358MB from your current installed RAM total; unless you assign a higher value via the BIOS or some sort of management software.

The 26MB reserved for hardware more than likely is being assigned to the GPU, because of all the eye candy that Windows 7 has. If you were to do something else, like he said, launch a 3D program, or a game that amount will go up to a max of 358MB.

 

[thecrafter]

I don't think 1 and 2 are correct, Telo

Dynamic Video Memory

Intel Graphics utilize a shared memory architecture (often referred to as a unified memory architecture or UMA) – system memory is used for both graphics and system purposes. Instead of using dedicated local memory, as is the case on the majority of discrete graphics cards today, a portion of the system memory is allocated to be used as video memory. Additionally, a small amount of system memory is permanently allocated to video memory by the BIOS. This amount is usually one or eight megabytes (most OEMs set eight megabytes). Systems shipping with a Windows Vista* logo are required to set eight megabytes of pre-allocated memory.

Dynamic Video Management Technology (DVMT) allows additional system memory to be dynamically allocated for graphics usages based o n application need. Once the application is closed, the memory that was allocated is released and is then available for system use. The purpose of dynamically allocating memory for graphics use is to ensure a solid balance between system performance and graphics performance. For example, if a user is simply editing text, there would be no need for the graphics to take up a large amount of the system’s memory. In such a case, it would be best if more memory was allocated to the system. On the other hand, if the user was to start up a 3D game, there would be a need for more of the shared memory to be used as graphics memory.

Windows Vista*

On systems running Windows Vista* the graphics driver will ignore the system BIOS settings for memory allocation due to differing operating system requirements from Windows XP. Instead the graphics driver will allocate a combination of fixed and dynamic memory based on the amount of system memory detected. This enables BIOS vendors to create a unified system BIOS for Windows XP* and Vista systems. A certain amount of fixed memory is required so that the driver can ensure a mode change from the current mode to any supported mode. For systems with 512 megabytes of system memory (minimum requirement for Windows Vista*) the driver will allocate 32 megabytes of fixed video memory (8MB from pre-allocated) and up to 32 megabytes of dynamic video memory for a total of 64 megabytes of video memory. If the system has more than 768 megabytes of memory then the graphics driver will allocate 64 megabytes of fixed video memory and the rest will be allocated dynamically depending on how much system memory there is. The chart below shows the specific memory allocation.

Source http://software.intel.com/en-us/articles/intel-gma-3000-and-x3000-developers-guide/

 

[thecrafter]

What confused me was you know how in Windows XP if you go to check your memory through system properties it would say something like 1.68GB instead of 2GB because it would just TAKE some of the memory needed by hardware/drivers? I guess they changed how it works in Vista/7 because in 7 it says I have 3.0GB installed (system properties) and as you see in the screenshot there, it shows all 3 gigs is showing as being available, instead of automatically subtracting 64-358MB from the total and pretending I have less memory installed

edit:

From the same document I linked above:

Windows XP*

On boot-up the system’s BIOS code determines the amount of system memory to be permanently used by the graphics controller and once selected, this memory will never be given back to the system. Some systems allow end users to adjust this value via BIOS setup options. Once the operating system is started the graphics driver will then dynamically allocate graphics memory based on requests from each application run by the user. For systems with more than 256 MB or more memory a maximum of 128 MB will be allocated for use by the graphics controller (memory set aside by the BIOS + memory dynamically allocated by the driver). In addition to this, a new BIOS setting can provide 128 MB of fixed memory or even 384 MB of memory for systems with 512 or more megabytes of memory.