First of all, here is my setup https://us.v-cdn.net/5021640/uploads/editor/6a/4oqwetjigvxj.png
I have 3 of these rigs. One of them are running perfectly, while the two others arent.
Now to my problem. Im having a hard time booting when all 6 gpus are connected. If i am able to boot, i usually only can see 4 gpus in device manager. Most of the time 1-2 of them have a yellow "!" next to it, with error Code 43: Windows has stopped this device because it has reported problems. Then screen flashes a few times and after a while the 4 listed gpus have no error.
So far i have flashed bios on all rigs. Updated widows, downloaded newest chipset drivers and gpu drivers. I have clean installed windows a few times, reset bios with CMOS pins a few times. I also have removed fast boot of in windows power options. In BIOS i have enabled 4G, Initiate Graphic Adapter to be IGD. Tried manually setting it to gen1, gen2 and gen3. Also tried all of my gpus and risers one by one (i did find a DOA riser). I know it should work, because as i said, one of my rigs are running prefectly.
I have no idea what to try anymore. i have had the componets for around 80 hours now, and i have invested around 60 hours looking on forums, trying out different and same things again and again with no luck.
I appreciate any help i can get.