Havo_k :
AC unity says otherwise. Anyways I prioritize my parts according to a chart:
1st priority:CPU, GPU and Motherboard are on the top
2nd priority: RAM and Cooling
3rd priority: Storage
4th: Drives and case
I feel like for a lot these new games that arent unoptimized well, only a good i7 (accompanied with good gpu) will get away without any or less issues. Games not getting optimized is getting very common.
I've gotta disagree with AC Unity. The power supply should be the biggest concern, because a crappy PSU can kill your entire setup. Then focus on a strong graphics card that fits your budget and your needs, OR a strong CPU that fits your budget and needs (because some builds need a i7 or even Xeon CPU and can use a 750Ti, for example, while others would benefit more from a GTX 980 and an lower caliber CPU in terms of price/performance), then focus on the other What i'm saying is decide if you need a good CPU or GPU, and choose the card/chip in that order). Then look for a motherboard that supports what yuo need, be it SLI/XFire, stability, overclocking, RAID, etc. RAM/storage/case are all looped into one final sategory, as these don't matter as much, but not one of them matter more than the other. A crappy case will hurt your temps, low performance RAM will hurt performance, and not enough or too slow drive impact your productivity.
As for optimization, if a game is optimized for and AMD chip, an i5 or i7 won't change the fact it's optimized for an AMD chip.