possible broken RAM?

[DaveMchuffner]

My computer has been running alot slower than usual recently and I've just found out that task manager is showing I have 16gb of RAM however it is only using 8gb.
i have tried changing the system config options and unticking maximum memory. I have flashed my bios to the latest update, checked to see if both sticks of ram are showing in the bios and also have changed the ram slots i use, nothing has worked. I'll attach all images i have of the bios and task manager.

Specs:

msi b450 motherboard
DDR4 cosair 3000
AMD ryzen 7 1700
 

[Otto_iii]

Can't say for sure, but yes it sounds like one of the sticks konk'd out and your running in single channel