Tomchew :
I suppose I should of mentioned it's mostly for gaming, I read in a couple places the i5 is the way to go as i7s don't give you that much more bang for your buck, but which i5 should I get, is the 8400 still that good?
At 1920x1080 you'll hit slightly higher FPS in a few games. At higher resolutions you likely won't see any differences. Long term the i7 will likely see a slightly longer useful life with gaming. Just as was seen with prior generations of i5 and i7.
As far as i5's go. Unless you get an 8600K/9600K with a Z370/390 motherboard and good heatsink. Then go ahead and overclock it. You aren't going to see much difference between i5 models. That extra $200 would be better spent on a much larger SSD so all your games can load quickly.
Really at this price level. You'll just be nitpicking. Any of these options will do well gaming and variations will just make minor differences. Once you have something like a Ryzen 2600/i5-8400 or better, GTX 2070 or better, good quality PSU and 16GB RAM. I'd be thinking more along the lines of:
- What sort of expansion and ports does the motherboard offer?
- Size and speed of storage devices?
- Noise generated by cooling equipment?
- Aesthetics of the system?
- What will improve the gaming experience? (Mouse, Keyboard, Joystick, Monitor, Speakers)