Bitcoin Mining Rig Freezes PCIe 1x - 16x risers

[AllenBTC]

Hi folks,

So I just started building my first mining rig.

Hardware is as follow:

msi B250 krait gaming mobo
Intel G3900 CPU
4GB DDR4 Ram
120GB SSD
MSI GTX 1070 x4 (for now)
Corsair RM1000X PSU
4 PCIe 1x - 16x molex to sata
Windows 10 64bit

So on the board 2 cards run just fine. As soon as I add all 4 cards to the risers the pc would freeze up and require a reboot. Sometimes happpens after 15min up to 10 hours before freezing. No black screen. Just plan not responding frozen screen and no mining.

I have updated BIOS to latest version. Drivers are all latest. All 4 cards are detected in device manager. I have also enabled Above 4G decoding in bios.

I honestly don't know what to do anymore. Is it the mobo, risers or mobo that does not work with the risers? Maybe just plain bad risers? Or a general issue others have as well?

Any feedback will be much appreciated.