Confused PCIe Slot

[Vipermk2]

As far as I knew your graphics card should be plugged into the first PCIe slot, however due to my cooler getting a little too close to the Card I have moved it down one into the PCIe 3.0 x8_2 slot. (which I initially thought was PCIe 3.0 x16_2 slot)

Am I totally misunderstanding how Graphics cards work but shouldn't it be running slower in the PCIe 3.0 x8_2 slot, or does it only become a x8 slot when the top slot is already already populated?

 

[AlienALX]

TBH it's all very bloody confusing. When I used the primary slot in both of my X99 boards my GPU ran at X8. When I moved it down to the middle slot on my X99 SLi Plus it runs at X16.

Download GPUZ, then click the ? next to where it lists your PCIE bus speed on the GPU. It will open a render test, simply watch what your GPU bandwidth shows with that test running.

 

[Vipermk2]

So it's ok on @x8 3.0

 

[AlienALX]

Does it not change when you run the render test? if so then yeah, it's running X8.

 

[Vipermk2]

It reads @x8 1.1 before the render. It must be fine as I'm getting the same frame rates as TTL did on his reviews of the card, if not a touch more.

 

[S_I_N]

theres a very marginal between x16 and x8 as far as performance goes. But if you want every bit of performance from it pop it in the 4th slot which read pci-e 3.0 x16/x8 3 slot. I looked at the back of the board and it is wired for x16