Only using 3.9 of 8gb of ram

bestanime

Prominent
Feb 3, 2018
11
0
510
So yeah as stated in the title im only using 3.9 gb of the 8gb that i have im thinking about taking it to a computer repair shop but wanted to know if there was any way to fix it before i do that.
My Specs
CPU:AMD - Ryzen 5 1600X 3.6GHz 6-Core Processor
MOBO: PRIME B350-PLUS ATX AM4 Motherboard
RAMCorsair - Vengeance LPX 8GB
Grapichs card:XFX - Radeon RX 580 8GB GTS Black
PSU:EVGA - 600B 600W 80+ Bronze Certified

some side notes: this all seemed to happen a couple of days after i installed my graphics by i couple i mean two iv also been getting 100% disk usage the new graphics card is the one i put in my specs