At long last, I may finally be able to upgrade my computer. Did some trawling around r/PCMasterRace to get a general idea on what I'd want/need for a computer to last me the next few years.
Gonna get a loan and spend like £300 of it on a mid-range gaming computer, should be able to easily out-perform current gen consoles which is good enough for me, it'll run Fallout 4 on Ultra 1440p at stable 30fps and GTA V on Ultra 1440p at average 40-50fps from the various GPU/CPU Benchmarks I've seen.
Although I may downgrade from 1440p to 1080p just for the extra frames, since there's about a 70% pixel density increase between 1080p and 1440p and I honestly don't care about the extra prettyness, 1080p is good enough.
One day when I'm super rich (Probably never) I'll buy a rig to run 3 4k monitors and never use two of them.