Hello Berkswolf, another blast from the past, Please leave any artic chill you have brought with you at my PC, I might want to use it later
As has been said previously CPUs haven't moved much in the last 5 years, if you have an overclocked I5 2500k or more modern CPU then it should still be OK. Consider getting more memory if you have less than 8GB and an SSD with good capacity - I have a 960GB on the main while secondary computer has a 250GB. These really do speed loading times.
Two GPUs rule the midrange, Last year's Nvidea Gforce GTX 970 is still damn good - I have one - and can propel lesser 3D games like Guild wars 2 to 4K @ 60hz. A single should be more than enough for 1080p with all the bells and whistles selected. We're expecting a replacement in the future as Nvidea has already launched a high end 14NM based gpu.
AMD Radeon RX480 is new out, it's much better than their previous offerings, up to the 970 at least but should be a little cheaper and less energy hungry. Based on new 14NM tech.
Which to go for depends on what motherboard you have, single slot doesn't matter, double graphics slot go with one that matches so you have the option of adding a second card. It shouldn't really be needed unless you have a massive screen resolution. A single one of these cards should be able to do very decent 2560x1440 (1440p) so you might want to think about a monitor upgrade.