Hello , my sister's laptop (Dell xps 15 9550) stopped turning on , I opened it , cleaned inside and laptop started working however I noticed as soon as I start using apps , computers gets super slow ! so after some research I found out when I go to task manager , the hardware reserved is almost 15gb out of 16gb . I tried to edit the registry and everything I could with no luck . then I opened the laptop and noticed when I take off one of the two RAMs the problem fixes . I tried every single RAM individually and also every dimm slot individually . Everything works fine individually and system reserve goes back to normal but when I put both of the RAMs in thats when the problem starts . Any idea on how to fix it would be appreciated