# Sensors: Memory Used vs Memory Usage (GTX1070)



## ADA (Sep 21, 2017)

What cases the "sensor" tab in GPU-Z look different (see attached image) on two PC with identical hardware and software configuration? On the left schreenshot the memory is "split" into Dedicated and Dynamic. On the right screenshot there is only one parameter called "Memory Used". What might cause this difference? How to configure GPU-Z to show the same parameters?

Used Setup:
Nvidia GTX1070 (vRAM 8GB)
latest driver 22.21.13.8541 from 21 Aug 2017
DELL Precision T5810, Windows 7
Latest version of GPU-Z 2.4.0
The Graphic Card tab shows identical properties for both GPU.

Why I am asking this question:
On the first PC a custom big-data scientific application crashes with a CUDA out-of-memory error. The "Memory usage (Dedicated)" goes up to 4GB and then the crash happens. On the other PC with the same hardware and software configuration the same application with the same parameters runs properly.  The "Memory Used" goes up to 8GB as expected.

Could the first graphic card be defect?

I would really appreciate any suggestions!








(Please note, I am not asking what is the difference between Dedicated and Dynamic memory. The screenshots were taken in the Idle state when the abovementioned application was not running.)


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## rtwjunkie (Sep 21, 2017)

Switch the graphics card between the two machines.  If the one gives the same 4GB message in a different unit, you will be well on your way to knowing the answer


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## ADA (Sep 21, 2017)

rtwjunkie said:


> Switch the graphics card between the two machines.  If the one gives the same 4GB message in a different unit, you will be well on your way to knowing the answer


This is a good suggestion, unfortunately I cannot switch the graphic cards as the machines are physiclly located in different departments. 

I would like to understand the difference between "Memory Used' and "Memory Usage" and how to force GPU-Z to show one or another, though. Figuring out if the first graphic card is defect would be just a bonus.


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## W1zzard (Sep 21, 2017)

The Memory Used (1 Sensor) is provided by the NVIDIA driver, if that can't be found GPU-Z will use a sensor from the OS (the one with two entries)


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## ADA (Sep 21, 2017)

W1zzard said:


> The Memory Used (1 Sensor) is provided by the NVIDIA driver,* if that can't be found* GPU-Z will use a sensor from the OS (the one with two entries)


 Is there a way to "enable" that sensor in the NVIDIA driver? The drivers on both graphic cards are freshly downloaded and installed. 

The Windows OS (also the process explorer) report only 4GB of dedicated memory on both graphic cards. (I have read somewhere that this might be a Win7 bug)


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## W1zzard (Sep 21, 2017)

ADA said:


> The Windows OS (also the process explorer) report only 4GB of dedicated memory on both graphic cards. (I have read somewhere that this might be a Win7 bug)


Yeah that's a Windows 7 issue



ADA said:


> Is there a way to "enable" that sensor in the NVIDIA driver? The drivers on both graphic cards are freshly downloaded and installed.


No idea how to enable the NVIDIA sensor. You can force the use of the Windows memory sensors by adding a registry key Force_WDDM_Mem_Sensor DWORD 1 to GPUZ's registry entries


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## Toma (Sep 22, 2017)

ADA said:


> The Windows OS (also the process explorer) report only 4GB of dedicated memory on both graphic cards. (I have read somewhere that this might be a Win7 bug)


M$ know about this bug in Win7 but  https://support.microsoft.com/en-us...iag-may-report-an-unexpected-value-for-th?p=1


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