Noted at many discussions at https://www.google.com/search?q=970+Pro3+R2.0+shows+only+8GB+usable+windows+10&gl=US
Read https://www.eightforums.com/threads/16-gb-ram-installed-but-only-8-gb-usable.57316/ and while it's W8, same screens for W10.
I've been unable to find a solution to anywhere else, so I'm hoping a discussion will help.
My computer reports that I have 16GB installed, but only 7.96GB is usable.
I'm using 4x OEM Kingston 4GB 1600 Mhz DDR3 Desktop RAM Memory PC3-12800 4G DIMM ram sticks. They're all identical.
My motherboard is an ASRock 970 Extreme3 R2.0 with the latest BIOS. I have had success with the following configurations with the modules:
-A1[populated] A2 [empty] B1 [populated]B2 [empty]
-A1[empty] A2 [populated] B1 [empty]B2 [populated]
Ensuring that all slots are operational. I've also tested each stick individually, and they all work.
The problem is, when more than 1 stick is inserted, I can never have more than half my installed RAM usable. I get the following results when I use different amounts of ram:
2x 4GB: "8gb installed, 4gb usable"
3x 4GB: "12gb installed, 8gb usable"
4x 4GB: "16gb installed, 8 usable"
And I've made sure to install them in the right modules.
Can anyone suggest some options on how to solve this? Please note, I've tried unchecking the "maximum memory" checkbox in msconfig already.
More information about my computer below:
OS Version: Microsoft Windows 10 Home, 64 bit
Processor: AMD FX™-8350 Eight-Core Processor, AMD64 Family 21 Model 2 Stepping 0
Processor Count: 8
RAM: 8148 Mb
Graphics Card: AMD Radeon ™ R7 370 Series Graphics, -1 Mb
Hard Drives: C: 1862 GB (1141 GB Free);
Motherboard: ASRock, 970 Pro3 R2.0
Antivirus: Windows Defender, Enabled and Updated

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