Would it be risky to use 6x 280x on a P9X79 Pro board?

Could I use 4 powered and 2 non-powered pcie risers?

I heard that PCIEx16 don't really need powered risers as the motherboard can supply 75W from that long slots.

Please enlight me!

[550 kH/s]

I'm running both in 1 call.

cgminer... -I 13,13 -g 2 -w 256 --gpu-engine ... --gpu-memclock ... --thread-concurrency 8192,8192 --expiry 1 --scan-time 1 --queue 0

I'm getting this hash rate:

280x - 725 kH/s
7950 = 550 kH/s 

My concern really is my 7950 which seems to be not utilizing its performance.

I did try to separate the batchfile but getting a lot of Pool 0 share became stale while retrying submit etc.

590 kH/s -> cgminer... -I 20 -g 1 -thread-concurrency 24000

Any suggestions?

Just started mining this month with LTC then shifted to DOGES