I've been working with some AMD motherboards without issues, but this MSI Z87-G45 Intel motherboard is giving me issue detecting more than 5 GPU's.
Setup:
- Motherboard: MSI Z87-G45
- CPU: Intel Celeron
- Memory: 4GB
- OS: Linux (BAMT 1.3)
- Risers: all 7 are 1x -> 16x risers, two are powered
- PSU: 2x 850w
- GPU: 6x Powercolor 7870, 1x 270x
This motherboard has 7 pcie slots. 4 1x, and 3 16x. Using just 3x16x does not work (3 cards, only 1 is detected). Using all 4 1x and the first 16x works (5 cards).
So all 1x slots work, only the first 16x slot works. I tried changing PEG 1-3 to Gen1, Gen2, Gen3, and Auto (default) to no avail. Two of the 1x slots have their risers powered (also works unpowered). No slots are shorted since all 1x slots work.
The BIOS has a feature where you can view all detected devices, and it only shows 5 cards even when 6 are installed (card in 2nd 16x slot not detected, moving it to 3rd 16x same thing) BAMT 1.3 shows the same (5 cards).
Cheers!
