Task Manager shows incorrect total system memory if 16-GB or 32-GB memory modules are installed

Applies to: Windows Server 2019 DatacenterWindows Server 2019 StandardWindows Server 2016 Datacenter

Symptoms


Consider the following scenario:
  • One or more 16-gigabyte (GB) or 32-GB memory modules are installed in a computer.
  • The computer is running a version of Windows that is listed in the "Applies to" section.
  • You view the Performance tab of Task Manager to view the total system memory.

In this scenario, you notice the following symptoms:

  • The total system memory or memory speed is listed incorrectly when you view the Memory category on the Performance tab of Task Manager. For example, on a computer that has 32-GB memory modules inserted into 21 slots, the total system memory is listed as "1.5 PB" (as shown in the following screenshot and circled in red) instead of the correct value of 672 GB (as shown correctly directly beneath the circled text).

    Performance tab
  • Information is also listed incorrectly when you rest the mouse pointer over the Slots used field. (This field displays the tool tip that lists the individual slots and memory modules.)
  • On a computer that uses 16-GB memory modules, the memory speed is listed incorrectly.

Cause


This problem occurs because of how memory is calculated from the System Management BIOS (SMBIOS) memory device information.

Resolution


This issue is fixed in Windows Server 2019, version 19H1 and later versions, and in Windows 10, version 19H1 and later versions.

Workaround


To verify the actual memory speed values, you can use Windows PowerShell to check the following properties (Windows uses these properties to report memory speed):

  • MaxSpeed
  • ConfiguredClockSpeed (used on devices that have 32-GB memory modules installed)

To do this, run a command such as the following at a PowerShell command prompt:

(Get-CimInstance -ClassName CIM_PhysicalMemory) | Select-Object ConfiguredClockSpeed, Speed

More Information


The memory results that are displayed by Task Manager are a cosmetic issue only and will not adversely affect the functionality of the operating system or applications.