Quote from: robbertone on January 30, 2014, 10:16:35 AM

I use the same board with 5 gpu's type r9 290 cards.

No shortening needed for a Asrock 970 extreme 4

I use two 16 x16 riser cables on the first en second 16x slots. The are working than at x8.

The last 16x slot can only be occupied with an 1x riser cable, because an 16 to 16x cable in this last slot would block the pcie x1 slots from working.
the other x1 slots can now work with x1 risers (see manual).

Install one by one starting with the first x16 x 16 cable than the other 16 x16 cable on the next 16 slot and than a x1 cable in the last 16 slot
Always easy continue to install in this hierarchy

It some time takes a lot of energy to customise a system.It is although strange that the same type of board is not always working the same way.

Good luck

I use X16 risers in all three X16 slots and I run 5 GPUs on this board. After building a few rigs for friends and my own few rigs I have come to the conclusion that each mobo / GPU is different and you just gotta see what it is gonna take to make your setup work.

One mobo want the X1 presence pins shorted one doesnt. One will run with all 5 cards on a 1.09V BIOS one wont, one wants powered risers in the X1 slots one doesnt care.

Just gotta figure it out. Easiest way is to pay attention and figure out what you have done already. Just going at it switching things around will get you no where and aggravate you. If you want to check the powered risers part then check each card remembering which ones you have done. Write it down so your not trying the same thing over and over again.

You have to figure out which combination of powered / not powered risers, presence pins, BIOSs, etc will work.