Already posted to /r/homelab but maybe this sub is actually a better fit. Original post below:

Currently in the process of upgrading my homeserver. I have four pcie cards I'd like to use with this board. Two intel i350-t4's, one LSI 9300-8i and one GT710 with a PCIe x1 connector. No matter what order I plug them in, I cannot get all of them to work at the same time. I can run the GT710 and the two intel cards just fine, but as soon as I plug in the 9300, one of the intel cards disappears and the 9300 is still not recognized, either.

I've tried pretty much every combination, I've tried manually setting bifurcation to 8/4/4 - nothing. The LSI card is working fine in another system, so it's not dead either and from what I've read so far, this should work. Am I missing something?

There's pretty much nothing else installed, except the cpu, a simple ssd (connected to the first sata-port) and a few fans.

Edit:

Just tested my old Dell H200, which is PCIe 2.0 whereas the 9300-8i is 3.0. The H200 works just fine, gpu, dual nics and all.