Is my Processor going to bottleneck me anytime soon?

Hey Guys! Over the years I have worked towards a decent gaming rig to run most of my games smoothly with decent fps and now I am planning on upgrading my graphics card to the high end of the current generation. I just want to make sure I'm not doing something stupid before spending a fortune on it. So here is my question: Is any component of my PC bottlenecking me and preventing me from getting the optimal performance of my rig? A few friends of mine told me that an AMD CPU doesnt pair as well with an Nvidia GPU as an Intel CPU and I want to clear the smoke and not listen to every rumor I hear.

My PC currently consists of:`

M5A97 R2.0 Mainboard

AMD FX-8350 Bulldozer Octa Core Processor @ 4ghz

16gb of DDR3 RAM running on 1333mhz (every other setting will freeze my pc after a few seconds, same with the processor, it seems to be very sensible to overclocking)

Radeon R9 280x Graphics card running on factory settings aswell

I'm currently using a 4k monitor and mostly play competitive games like Dota 2, Overwatch and CS:GO, but I have to lower the render scale on Overwatch and Dota to make it run on 4k with 60fps. Since I want to play Star Citizen with a decent Framerate on at least 1080p I'm planning on getting myself a GeForce GTX 1080. What do you guys think?