Pc has and recognises 16gb ram but windows only uses 8

[agent_x007]

But you can read what it says on the screen no? That means the RAM is working, as the system is detecting 16 GB.
I've had this exact issue and I'm not alone.

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Had this with damaged stick (no boot with single stick, unstable at stock clocks with two stick inserted), damaged board (bad contact on socket pins), when one pin was missing on CPU, and when overclocking IMC/Chipset and/or RAM too hard.

 

[TheLostSwede]

Had this with damaged stick (no boot with single stick, unstable at stock clocks with two stick inserted), damaged board (bad contact on socket pins), when one pin was missing on CPU, and when overclocking IMC/Chipset and/or RAM too hard.

Wow, you really like wreacking your hardware, do you?

I've only ever had this happen once and there was nothing wrong with any of my hardware.

 

[agent_x007]

Not really ?
Most of those were hardware I bought that was sold very cheap locally as "not tested", or a seller simply ommiting some "issues" from describtion.

 

[z2x1]

well guys it seems like it's a hardware issue so i just bought a silicon power stick 8gb ddr4 at 2666mhz cl19 for 35 leva or 17,5 euro and it works dual channel even managed to clock both sticks to 3000mhz