Traditore :
bjornl :
The CPU should be ok. But your PSU is an issue.
The motherboard does not allow for overclocking; If you want to buy an unlocked motherboard with that in mind, you'll need to swap the motherboard as well. If you just want a faster processor and don't want to overclock, then any i5-7xxx or i7-7xxx will work. The unlocked ones are faster even if you don't want to over clock. I suggest you run the system before you decide.
The power supply sounds like a pile of poo. They don't mention the brand. The wattage is the bare minimum to turn on that video card. Make this your first upgrade. Use this as a rough guide to quality PSUs. I would suggest a 550-650watt one.
1070 draws 200W in 4K gaming. How is 450 not enough?
http://www.tomshardware.com/reviews/nvidia-geforce-gtx-1070-8gb-pascal-performance,4585-7.html
It is a generic POS PSU. So not going to provide 450w. It will be at max efficiency at between 20-80% usage at which it will provide less than 80% of the rated power. You will not get more than 275-320w out of it in all likely hood. Right on the edge.
example: if it is running at 80% of capacity (or 360w) it is unlikely to even deliver 288w (max efficiency for these off-off brands is 80%). It is more likely to be producing 75-77% of power. As power usage climbs over 80% efficiency will drop ever lower. And the quality of this power won't be good.