Can I leave a PCI-E lane between my GPUS?

[Spratster]

I'm doing a build with two GTX 980 STRIXes on the Asus X99-Deluxe (https://uk.pcpartpicker.com/part/asus-motherboard-x99deluxe) and am curious as to if I can leave a gap of one PCIe lane between them? The strixes are pretty tall, and the PCIe lanes are pretty close together and while they do fit together in the top two adjacent PCIe 16x lanes, I fear the upper one may suffer tremendously due to lack of air with the fan being just a couple of millimeters away from the lower cards backplate. If I put them adjacent, would I really have any issues with cooling? If I left a gap of one PCIe lane between them, would there be any disadvantages?(e.g. performance, airflow). Incase* it matters I'm doing the build inside a H440.

*See what I did there?

P.S. I'm not sure if i'm spelling PCIe correctly, if not please correct me too.

 

[gilbadon]

youre fine

 

[Spratster]

youre fine

Lol, next?

 

[gilbadon]

Ugh.... all of the PCIe ports run at x16. You are limited to a specific number of lanes (40) but the order in which you put those cards does not matter because each port is equal to one another. Put the cards where ever you want, they will both run at x16 & x16. If you add another card the third will run at x8 but placement will still not matter.

 

[Mac266]

Yep, It'll work. The Motherboard might automatically set it to PCIe 3.0 x8, but that won't make a difference anyway.

 

[Spratster]

Ugh.... all of the PCIe ports run at x16. You are limited to a specific number of lanes (40) but the order in which you put those cards does not matter because each port is equal to one another. Put the cards where ever you want, they will both run at x16 & x16. If you add another card the third will run at x8 but placement will still not matter.

Thank you! that's a lot better, appears you also learned English grammar in 5 minutes, astounding!

 

[Spratster]

Yep, It'll work. The Motherboard might automatically set it to PCIe 3.0 x8, but that won't make a difference anyway.

Thanks, but are you sure about the x8 thing? It my sound dumb but why would they include x16 if even the highest end gaming gpus don't benefit?

 

[Kari]

40-Lane CPU-
5 x PCIe 3.0/2.0 x16 (x16, x16/x16, x16/x16/x8, x8/x8/x16/x8, x8/x8/x8/x8/x8 mode)

28-Lane CPU-
3 x PCIe 3.0/2.0 x16 (x16, x16/x8, x8/x8/x8)

so yeah, it'll depend on your cpu whether the second card will run at x16 or x8, performance difference will be minimal however...

 

[Spratster]

40-Lane CPU-
5 x PCIe 3.0/2.0 x16 (x16, x16/x16, x16/x16/x8, x8/x8/x16/x8, x8/x8/x8/x8/x8 mode)

28-Lane CPU-
3 x PCIe 3.0/2.0 x16 (x16, x16/x8, x8/x8/x8)

so yeah, it'll depend on your cpu whether the second card will run at x16 or x8, performance difference will be minimal however...

Okay cool thanks, out of curiosity, I'm running a 5930k, how many lanes is that thing?

 

[gilbadon]

40-Lane CPU-
5 x PCIe 3.0/2.0 x16 (x16, x16/x16, x16/x16/x8, x8/x8/x16/x8, x8/x8/x8/x8/x8 mode)

28-Lane CPU-
3 x PCIe 3.0/2.0 x16 (x16, x16/x8, x8/x8/x8)

so yeah, it'll depend on your cpu whether the second card will run at x16 or x8, performance difference will be minimal however...

Okay cool thanks, out of curiosity, I'm running a 5930k, how many lanes is that thing?

40!

 

[Kari]

see the page 1-13 in the manual
http://dlcdnet.asus.com/pub/ASUS/mb/LGA2011/X99-DELUXE/e9504_x99-deluxe_series_ug_for_web_only.pdf

it seems the mobo actually wants you to use the x16_1 and x16_3 slots in dual card setup, so the x16_2 slot is indeed unused in the middle (+ the little slot that gets blocked by the 1st card anyways)

 

[Jonathan Cave]

 

[Kari]

^yes thats the table i was looking at, thx for the screenshot 😀