CPU Recommendation for H81 PRO BTC

Hi everyone,
I bought RX 480's and working on my rig right now. I need some recommendations for MB and CPU. I can buy H81 Pro BTC for very good deals, but I don't know which CPU should I buy. Many miners suggests G1820, but since it's also kinda old, it's hard to find. Can you suggest me some good motherboard AND CPUs for 6++ GPU Mining? I bought MSI Z170A Krait Gaming 3X before and I couldn't even boot with 4th GPU. (faced with PCIe lane problem)

I found a list like this;

7PCI
MSI Z97 GAMING 5
MSI Z87-G45 Gaming
MSI Z87 MPOWER
MSI Z77A-G65 G45
MSI Z77 MPOWER

GIGABYTE GA-Z170X-Gaming 6
GIGABYTE GA-Z170X-Gaming 5
GIGABYTE GA-Z77X-UP7
GIGABYTE GA-X99-UD3P
GIGABYTE GA-X99-UD4P +m2
GIGABYTE GA-X99-GAMING 5

ASUS Z97-PRO
ASUS Z87-PRO

ASRock Z170 Extreme3 LGA 1151
ASRock Z87 fatal1ty
ASRock Z77 Extreme11

BIOSTAR RACING Z170GT7

6PCI
MSI Z97 GUARD-PRO
MSI Z170-A PRO
MSI Z170A SLI
MSI FXA-GD65

GIGABYTE GA-Z170X-Gaming 3 (2x m2)
GIGABYTE GA-Z170X-UD3
GIGABYTE GA-Z170X-UD5
GIGABYTE GA-Z170-Gaming K3
GIGABYTE Z87X-UD3H

ASUS H170 PRO GAMING
ASUS CROSSBLADE RANGER A88X

ASRock Z170 Extreme3 +m2
ASRock H97 Anniversary
ASRock H61 PRO-BTC
ASRock H81 PRO-BTC
ASRock H81 PRO-G

BIOSTAR:
Hi-Fi Z87X 3D
Hi-Fi Z77X
Hi-Fi A85X