Question 16GB Ram Installed, 7.9GB Usable, 8.1GB Hardware Reserved

[DarkmatterV1]

I built a new PC a while back and noticed that only half of my ram was usable, but never felt the need to fix it, but I've been having trouble with having too little memory lately, so here I am.

Task manager notices that 16GB memory is installed, but shows 8.1GB to be hardware reserved. (It also notices that 2 slots are being used)
see:

https://imgur.com/kFkz515

View: https://imgur.com/kFkz515


I have checked BIOS and it states "Total Memory" to be 8176MB (DDR3 1600MHz), though in the ASUS SPD Information tool, both slots 2 and 4 show information for the installed RAM sticks.

Additionally, I checked the CPU-Z tool, and it shows memory to be booted in single channel mode? Yet in the SPD tab both slots 2 and 4 show information for the installed RAM sticks (as above).
see:

https://imgur.com/S2knt6K

View: https://imgur.com/S2knt6K


Specs:
MOBO: M5A99X EVO R2.0 CPU: AMD FX-8350
GPU: NVIDIA GeForce GTX 1060 6GB
RAM: Corsair Vengeance 16GB (8GBx2) memory kit, part #CMZ16GX3M2A1600C10
OS: Windows 10 Home x64
BIOS Version: 2005 x64 (09/16/13)

Things I have already tried:

Untick max memory in msconfig advanced boot options
Reseat RAM sticks, check each stick individually
Resetting BIOS to default settings

Notes:
Both sticks boot by themselves in slot 2, no boot if one stick placed by itself in slots 3 / 4, and slot 1 is covered by heat sink so its inaccessible. I assume this means that both sticks are still good, but does no boot in slots 3/4 indicate that those slots are dead/broken?
If so, why is the stick still recognized when seated in the slots when using slots 2/4 or 2/3 and not just slot 3/4 by themselves? Is there any other way of checking that each slot is functioning as needed?

What should I do?

 

[richiestang_78]

You should install your RAM ins slots 2 and 4 in order to get Dual Channel.

Next in the search bar type msconfig-->Boot-->Advanced Options then make sure the maximum memory is set to 0.

Also found a couple forum posts of people who said if you swap the stick locations that can fix the error as well.

 

[DarkmatterV1]

My apologies for not making it clear, but I do have my RAM installed in slots 2 and 4, yet CPU-Z still says single channel mode is being used.

Maximum memory is set to 0 in msconfig->boot->advanced options

I have tried the following stick positions/swappings. Here are the results for each:
Two sticks (naming them A/B to distinguish between them)
Config 1 (And current): Stick A in slot 2, Stick B in slot 4 --> only 8gb usable of 16gb installed
Config 2: Stick B in slot 2, Stick A in slot 4 --> only 8gb usable of 16gb installed
Config 3: Stick A in slot 2 --> 8gb usable, 8gb installed
Config 4: Stick B in slot 2 --> 8gb usable, 8gb installed
Config 5: Stick A in slot 4 --> No boot
Config 6: Stick B in slot 4 --> No boot
Config 7: Stick A in slot 3 --> No boot
Config 8: Stick B in slot 3 --> No boot

I'm not sure if this means that slots 3/4 are dead or not. I would assume it does, however, because in configurations 1 and 2 when I check BIOS i can still see the details of the stick placed in slot 4, which i assume would not happen if the slot were dead. Additionally, windows can still see that there are 16GB installed, its just that only 8gb is usable.