400 dollar

Budget: 400$ The current MOB that I have I think my best option here would be getting a AMD Ryzen 7 2700x with a MSI Proseries Am I making the right decision?

My monitor is an ASUS VG248QE, when I try switching from HDMI to DVI I see my desktop but without my apps and whenever I click on something from my taskbar, nothing from there opens. I need to know how to fix this in order to get 144 hz. How do I fix this please? Weirdly enough, when I took a...