Question BIOS displays RAM installed but not enabled

[LSmizay]

I have had my desktop for a while but just started working from home. I am attempting to do a RAM upgrade and cannot get all 64GB. I have working combos, but if I place 4x16GB RAM the computer will not turn on. I installed the RAM and reset the CMOS and it did nothing. All the RAM is DDR3 1600MHz. Any assistance would be appreciated.
The motherboard is a GigaByte F2A88-D3HP
The processor is an AMD A6-7400K
Scenario 1 I replaced DIMM slot 1 with an old 8GB and I only get 24 GB / 56GB
Scenario 2 I replaced DIMM slot 1 & 3 with an old 8GB and I only get 16GB / 48GB
Scenario 3 I replaced DIMM slot 1 & 3 with an old 8GB and DIMM slot 2 with a 4GB and I get the full 36 GB that is installed
Scenario 4 All 4 DIMM slots 16GB and the computer won't power on

 

[Lutfij]

Welcome to the forums, newcomer!

Can you please state the specs to your build like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:

Include the BIOS version for your motherboard at this moment of time. Please include the rams/ram kits you're working with as well.

All the RAM is DDR3 1600MHz.
If they are mixed and matched, that's your first problem.

 

[LSmizay]

Hello! I want to put out there this computer was built by my son in 2016 and I bought it from him for $50 when he was moving out. Which is to show how old and how much I know about it. The issue is I cant get 4x16GB of cheap RAM to work. I attached pics of what I see in the BIOS. I am currently running pic 3. Pic 1 is the way I initially able to get the PC to power on.

CPU: AMD A6-7400K
Motherboard: GigaByte F2A88-D3HP
BIOS: F2
Ram: Currently 36GB 2x8 G Skill, 1x4 Samsung 1x16 Festive (trying to get to 64GB 4x16 Festive)
SSD/HDD: Samsung EVO SSD
GPU: NVIDIA GTX760
PSU: Just says 430 on it
Chassis: Unknown (it was the cheapest on NewEgg in Nov 2016)
OS: WIN 10
Monitor: Samsung C32R502FH

https://ibb.co/jzLhtXC

2 hosted at ImgBB

Image 2 in Leonard Smith's images album

ibb.co

https://ibb.co/HFf6DJJ