$1400 6 RX 570 4GB cards
$300 1200W EVGA P2 PSU
$80 ASRock or Biostar 6 PCI-e mining motherboard
$55 Pentium CPU
$35 4GB RAM
$20 32GB USB Flash Drive
$45 6 powered risers
= >$2000
That rig will easily give you 168 MH/s on ETH with 4300 MH/s on DCR dual mining or 1800+ H/s on ZEC and a faster ROI for more profit. For the same $1400 spent on cards, you can only buy two 1080 Ti, which won't come close to the six RX 570 4GB cards in mining performance.
For around $2400 (probably a bit less), you can build a NON-RISER 3x 1080ti rig - use one of the Zotac shortie cards in the 3'd slot to let the middle slot card cool, and a pair of Gigabyte Windforce full-size cards for the other 2 slots.
Ballpark 2200-2300 hash/s on ZEC and don't have to count on FINDING cheap RX-series cards that are commonly "LIMIT 1 per 48 hours" when you can find them in stock AT ALL for under $300.
Expecting to find RX-series cards at $233 each is a pipe dream anyway at this time.
I can order
3 x 1080 ti's for 2070
1 x z270 mobo for 100
1 x 850 watt psu for 130
1 x 8gb stick of ram for 60
1 x cpu g4400 for 55
1 x usb 64gb usb stick for 20
1 x riser for about 15
total of about 2500
put it on paypal six months to pay
have the gear by friday
mine about 2200 sols for zec earn 12 a day
spend 600 watts or 1.50 a day for power at 10 cents this is 10.50 profit per day
no money out of pocket and don't have to pay for 180 days.
this is not a burst bubble. it is a deflating ballon.