I have 16GB of RAM installed in my pc and only 7.9GB available, as task manager says 8.1GB is reserved for hardware. My system is only approx. 1 1/2 years old at most and this issue came up fairly recently. I have a Ryzen 5 1600 and a ASRock A320M-DGS motherboard, with Patriot Viper DDR4 RAM. Can anyone help?