Hello,

RX 470's (bios modded)
Z170A Motherboard (Gen 1 and 4g enabled)
4GB Ram
128GB SSD
Windows 10 (early version. I'm having a hell of a time upgrading to 1709. Trying again as I write this.)
Crimson 16.11.5 (pixel patched)

It mines perfectly with 4 cards. I add the 5th and its detected fine but crashes when I start the miner. No blue screen. The mining software just locks up and then the computer freezes and I need to reboot. I'm mining cryptonight and I get the same result on claymore, sgminer and xmr-stak. I can keep the 5th card in and remove a different card and it mines fine.. so I assume the card, riser and slot are fine. One time I was able to get claymore mining with all 5 but the 5th card wasn't hashing. I've tried dmem 0, a lower h value and even lowering the power limit.

Any ideas?

Thanks