Claymore's sequence is finicky, it doesn't always show the order correctly. For GPU-z and Watttool, they should both show the same order, and NORMALLY, it's the order that they're plugged into the mobo, but again, I'd suggest just using what I said to make sure.
These are the order for 2 of my rigs
GPU-z Wattool Watttool Index PCI-e Claymore power voltage mem voltage
1 0 0 1 75 910 900
4 1 2 3 910 900
2 2 4 5 910 900
3 3 6 2 910 900
0 4 8 4 910 900
5 5 24 0 910 900
How do I find out?
I change frequency in watttool from say 2125 to 2126. Then I look around at GPU-z to see which changes. Then I jot that down. Then I turn off some card in claymore.
Finally, I turn off some card in claymore and go look at the machine. After a WHILE, the card that is off will have the fan stop working.
The order is always the same for both of my rigs.
The only things that changes is the watttool indexes. It's
0
2
4
6
8
24
In others it's
0
20
8
14
2
36
Also the 5th card in wattool is always the card that is on PCI-e 16x. It has samsung memory that should have 30.5 mh/s. However, it only clocks 28.5 mh/s
I have no idea how. If I get rid the 4 hynix card, the one with samsung will give 30.5 mh/s for ethash as expected. Put 4 hynix memory and that card performance drop
ETH - Total Speed: 170.771 Mh/s, Total Shares: 391, Rejected: 0, Time: 02:48
ETH: GPU0 29.342 Mh/s, GPU1 30.586 Mh/s, GPU2 23.229 Mh/s, GPU3 29.316 Mh/s, GPU4 28.970 Mh/s, GPU5 29.328 Mh/s
ETH: 04/23/17-10:55:09 - New job from europe.ethash-hub.miningpoolhub.com:17020
ETH - Total Speed: 176.632 Mh/s, Total Shares: 391, Rejected: 0, Time: 02:49
ETH: GPU0 29.299 Mh/s, GPU1 30.540 Mh/s, GPU2 29.306 Mh/s, GPU3 29.329 Mh/s, GPU4 28.865 Mh/s, GPU5 29.295 Mh/s