Question Windows only recognising half the installed memory

[langolyers]

I've searched all over the place and found threads with similar issues, but haven't found a solution yet, so hopefully someone can help me.

My specs:

Gigabyte AB350-GAming 3
Ryzen 5 2600 3.4 GHz
Corsair 16GB (2x8GB) CMK16GX4M2C3000C16 DDR4 3000 MHz
Geforce GTX 1070
Crucial BX100 500 GB (Ubuntu)
ADATA SX6000PNP 1TB (Windows 10)

I bought the ADATA SSD and did a fresh install of Windows 10 on it, after which I noticed Windows was using only 8 GB of my 16 GB of RAM, with another 8 GB reserved for hardware.

After updating the BIOS, Windows doesn't show hardware-reserved memory any more, but is still capped at 8GB. On the other hand, the BIOS, CPU-Z, memtest and Ubuntu all recognise the 16 GB. Here's what I've tried, to no avail:

• Updated BIOS to latest version
• Checked maximum memory on msconfig: it was already unticked. If I tick it, it only allows 8192 maximum.
• Reduced memory frequency to 2133 MHz
• Re-seated the sticks
• Ran memtest overnight - no errors
• Ran memory diagnostic tool - no errors
• Turned off auto RAM virtualisation

I'm out of ideas, truly appreciate if someone can help me.

 

[langolyers]

Got it fixed. Not sure what exactly solved it, but I tested every ram stick in every slot to see if there was a fault, there wasn't. Then I went to the BIOS and disabled and re-enabled XMP (again). Now Windows can see both sticks correctly again.