Originally Posted by Jeffinslaw
Yes. Few things, had to change PCIe to gen1, primary card can't be on a riser for some reason, doesn't matter if it's X16 to X16 or X16 to X1 in any slot on the board, it will not boot.
Other than that, I have 4 out of 5 cards running. Will be switching to Ubuntu today to get better hash rates and the 5th card detected. Currently running Windows 7 Ultimate.
I have 5 gpus running, I have changed PCIe to gen 1. I have all my cards on risers 1x to 16x it boots fine for me. But If i try to use the 1x slots that when things get messed up. Currently I am running all cards out of the PCIe 16x lanes.
3 r9 270s and 1 7990
This is what it says on gigabytes website
3 x PCI Express x16 slots, running at x16 (PCIEX16_1~3)
* For optimum performance, if only one expansion card is to be installed, be sure to install it in the PCIEX16_2 slot.
2 x PCI Express x16 slots, running at x8 (PCIEX8_1~2)
* The PCIEX8_1 slot shares bandwidth with the PCIEX16_1 slot and the PCIEX8_2 slot with PCIEX16_3. The PCIEX16_1/PCIEX16_3 slot will operate at up to x8 mode when the PCIEX8_1/PCIEX8_2 is populated.
(The PCIEX16 and PCIEX8 slots conform to PCI Express 3.0 standard.)
* Whether PCI Express 3.0 is supported depends on CPU and graphics card compatibility.
* The PCIEX16_2 slot will become unavailable when an expansion card is installed in the orange PCI Express x16 slot.
2 x PCI Express x1 slots
(All PCI Express x1 slots conform to PCI Express 2.0 standard.)