Build check please!

[Manlost111]

I'm thinking of buying a system to start some mining and so far, this is what I've come up with:
Intel Celeron G3930
4GB Corsair Value Select RAM
120GB Kingston A400 SSD
MSI 270 PC Mate

I've opted for the MSI board because it has diagnostic LEDs in case something goes wrong on the setup. I build my own gaming PCs and I really like this feature on the motherboards. However, if there are any other motherboard suggestions, I'm open to suggestions!

What I can't decide on is whether to buy 6x 1070s or 6x 580s 8GB cards. I can totally see the value of the 580s as on the price difference alone, I could buy 3x more 580s, but I'm also looking at resale value a year from now and I'm thinking 1070s can hold value better? I'm usually Team Green on my gaming PC.

With the indecision on the GPUs, I'm also left wondering about how to calculate requirements for power needs. The TDP for the cards seems to be 215W for 1070s and 185W for 580s which seems odd as I remember reading reviews where the Intel cards are supposed to pull less power. Searching on the internet gives vastly different numbers as well. Any advice on how to do this? If the 580s do indeed pull 185W, it seems like I'll be needing 2x PSUs regardless of which GPU I'll go with, correct? I'm not comfortable pushing my PSU to the limit, so even if a GPU can support 6 cards at 90% capacity, I'd rather buy a 2nd PSU.

I keep hearing about cryptocurrency and would like to try it for myself.... if things don't work out, I'll be flogging this on eBay or some site later on and try to reduce my losses.... if they do, then cool! I do know how to build PCs as I've built my own gaming PCs for more than 10 years now but building for mining is a totally different aspect for me.

Any advice on this build would be greatly appreciated! Thanks and Merry Christmas to all!

[MATHReX]

I can recommend ASUS-Z270P as a motherboard because it is my go-to for any mining rigs.
It all depends on cheap price, if you can get a GPU for a cheaper price, that means quicker breakeven so RX 5XX will be good.
RX 5XX can make $2.5-3 a day before electricity cost, so if you can get it in the price range of $300-350 per piece meaning a solid break-even of a mere three months.
Not taking into account of price increase which will further reduce break-even period.
Go with 9x RX 5XX series and select ASUS or BIOSTAR Mining motherboard so you won't require additional M2 adapters for 8+ GPUs.
As Power consumption goes, a single RX 5XX series will consume around 120-130W dual mining.
So, 1600W PSU should be more than enough to power the rig.
I'll suggest going with dual PSU set-up for that kind of power requirement or Server PSU.