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I have an MSI B450M PRO-VDH MAX motherboard with Ryzen 2400G and 8gb Corsair Ram Part Number - CMK8GX4M1D3000C16,in bios i was using XMP profile 2.

Today i bought another 8gb ram but in taskmanager there was only 13.9gb usable and 2.1gb was hardware reserved. I disabled integrated GPU and everything but it did not reduce the system reserved memory . I also tried motherboard default settings and none solved it.

Then i disabled integrated GPU, disabled XMP and now 15.9gb ram was usable but the RAM speed shown is 2133MHz (but its 3000MHz ram, right?). But whenever i try to use XMP (any profile), 2.1gb will be system reserved. Then i have to reset motherboard settings to default settings and disable those things to use all available ram. Any answer as to why it is like this? and please suggest a fix.

Paul
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The B450M PRO-VDH MAX specifications say:

- 4 x DDR4 memory slots, support up to 128GB *ComboPI 1.0.0.3-based and above BIOS are required.1
  - Supports 1866/ 2133/ 2400/ 2667Mhz (by JEDEC)
  - For AMD Ryzen Gen3 (R5/R7/R9)
      Supports 2667/ 2800/ 2933/ 3000/ 3066/ 3200/ 3466/ 3733/ 3866 MHz (by A-XMP OC MODE)
  - For AMD Other Processors
      Supports 2667/ 2800/ 2933/ 3000/ 3066/ 3200/ 3466 MHz (by A-XMP OC MODE)

Since your CPU MD Ryzen™ 5 2400G with Radeon RX Vega 11 Graphics, is Gen2, the most it can do is 2667Mhz.

The tech-specs of your CPU say:

SPD Speed 2133MHz
Speed Rating PC4-24000 (3000MHz)

"SPD Speed" means Serial presence detect, which means:

In computing, serial presence detect (SPD) is a standardized way to automatically access information about a memory module.

In other words, this is the information that the BIOS will see and which it will communicate to the operating system. The only way to override it, is to either manually choose an XMP profile, or to modify the hardware parameters.

Modifying these parameters is a complex procedure. If you follow it, expect boot failures. Some understanding of the complexity involved you may find in the thread For Those Who Don't Know What SPD memory speed is for. I don't really recommend going this way.

For your problem of Hardware reserved memory, this is memory is generally a part of shared VRAM (graphics memory).

However, there is no explanation as to why when jacking up the RAM frequency you find yourself with less RAM than before.

The only explanation I can think of is that one of your RAM sticks is faulty and cannot work correctly under the XMP setting that you chose. You may try to insert the sticks one-at-a-time under this XMP setting, to see if both function correctly.

harrymc
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