PCIex slot1

[catkicker]

Not sure if this should be in motherboard or graphics card section. So I'm getting a rig together for my son, (Thanks again for the help with raid setup) Now I had a small nvidia graphics card in PCIex2 for initial testing and setting up computer.
I installed the GTX970 and computer hangs on debug 96 pulled it out reinstalled checked cables, no good. Jerked around with it even tried a 780Ti no luck but that little BS graphics card works fine in the PCIex2 slot
So I moved the GTX970 to PCIex5 slot and WA LA! it boots and works fine. Either the big cards are not properly seating in the PCIex2 slot or it's partially hosed.

So the question is....Does the GTX970 get full performance, 16 lanes when it's installed in PCIex5 slot

Motherboard; Asrock Z97 Extreme 4
Graphics; Nvidia GTX970
Power; Corsair 850W

Specs from motherboard say

3 x PCI Express 3.0 x16 Slots (PCIE2/PCIE5/PCIE6: single at x16 (PCIE2); dual at x8 (PCIE2) / x8 (PCIE5); triple at x8 (PCIE2) / x4 (PCIE5) / x4 (PCIE6)- 3 x PCI Express 2.0 x1 Slots

 

[EarthDog]

The second slot (PCIe 5) will be x8 according to that passage. You really won't be losing anything (1%) using an x8 slot with a 970.

Is the BIOS updated on the motherboard?

If you can see the back of hte motherboard (in pictures) does the soldering go halfway through the slot or all the way? I don't think the slot is even wired for x16 it has to be x8 max. You could also see what it runs at if you have GPUz installed as it shows the link speed.