PCIe CPU lanes vs Chipset lanes for NVMe - any difference in gaming?

[Gessler555]

I'm planning to get a ROG Z790-E Gaming WiFi II board which comes with 5 x M.2 slots. I have a 980 Pro NVMe (500gb) that I want to be my boot drive and I'm planning to get a 2tb 990 Pro NVMe (or WD SN850x) for my games & files.

 

From what I heard, populating the topmost slot (marked M.2_1) which supports PCIe 5.0 would mean my GPU would no longer get x16 lanes, even if I'm only putting a PCIe 4.0 NVMe like my 980 Pro in that slot (correct me if I'm wrong on that). So I'm putting my boot drive in the M.2_2 slot, fine.

 

But those two are the only slots that talk directly with the CPU, rest all go through the chipset. So if I put my games drive on any of the other 3 slots, am I losing anything with regard to speed or otherwise?

 

Sorry for the stupid question, I'm not well versed with how exactly the PCIe lanes work and what effect if any it's going to have on my read/write speeds or just general game performance.

[GuiltySpark_]

 

6 minutes ago, Gessler555 said:

From what I heard, populating the topmost slot (marked M.2_1) which supports PCIe 5.0 would mean my GPU would no longer get x16 lanes, even if I'm only putting a PCIe 4.0 NVMe like my 980 Pro in that slot (correct me if I'm wrong on that).

Correct.

 

6 minutes ago, Gessler555 said:

So I'm putting my boot drive in the M.2_2 slot, fine.

Yes.

 

6 minutes ago, Gessler555 said:

So if I put my games drive on any of the other 3 slots, am I losing anything with regard to speed or otherwise?

No, not in the real world. If this is a gaming PC, there is essentially no chances of that being an issue. You'd have to be moving some serious data between other devices connected to the chipset for that to ever be a concern. 

[Blasty Blosty]

@GuiltySpark_ so if I put a gen 4 drive in my motherboard's top slot (B650E-F), would my GPU be affected?

[Doobeedoo]

So far not really, I used one in main slot later moved it on other slot and loads were same. Now, in time once games fully start to utilize modern SSDs with DirectStorage we will have to compare then.