Do you guys think PCIe 3.0 will bottleneck the 3080 Ti/Big Navi?

Hey guys!

So I rewatched Steves "5500 XT PCIe 3.0 vs. PCIe 4.0, Hamstrung by PCIe Bandwith?" video, and there's a slight bottleneck with a fairly entry level GPU, and if I'm correct Steve explained this with two things: First, the 5500 XT uses PCIe 8x instead of 16x.
Now that itself shouldn't be a bottleneck IMO, because there was a techpowerup article that shows that even the 2080 Ti is barely bottlenecked by PCIe 3.0 8x (2-3% depending on the resolution).
The other explanation was that the 4 GB version running out of VRAM.

Now my situation is, I bought a 9900K back in november 2018 soon after it was released (I know Zen 2 is better value, but even the first adoredTV rumors weren't out at the time I bought this CPU and it is clearly faster for gaming then the 2700X), and I usually keep my CPUs for 2 generation of GPUs, while get the new Ti class GPU every generation. So when the 3080 Ti comes out (or big Navi, I'm not an Nvidia fanboy, if big Navi can beat the 3080 Ti then I'll buy big Navi) I'm planning to get it and use it in my 9900K system.
Since I play at 4K and Ampere is rumored to do RTX way better I think the 9900K won't bottleneck in 4K max settings with RTX on, even if the 3080 Ti is insanely powerful I don't think it will be able to do more then a 100 fps in new titles with settings like this, and the 9900K should be able to keep up with that (also I would have to buy a new mobo again to upgrade, Comet Lake just doesn't worth it at all, and if I would go with Zen 3 I would still need a new mobo, Zen 4 will again need a new socket but I think both that and also LGA 1700 is rumored to have a decent support + DDR5 and maybe even PCIe 5.0 so I was thinking I would upgrade to either Zen 4 or Alder Lake depending which is better for gaming).

So my problem is that Z390 and the 9900K only supports PCIe 3.0 (and even Comet Lake is on PCIe 3.0).
I'd imagine the next generation GPUs will all be on PCIe 4.0 since Navi is already on 4.0.
The techpowerup article showing that the 2080 Ti is just barely bottlenecked by PCIe 3.0 x8 gives me some hope, thinking that you would need a GPU twice as powerful then the 2080 Ti to be bottlenecked by PCIe 3.0 x16.
On the other hand, the 5500 XT situation shows how it's not as simple as I tought.
So a 3080 Ti will definitely be on x16, also I'd imagine it will have loads of VRAM, so it won't have the issues the 5500 XT has, but it will be way more powerful OFC, also I don't know if the extra RT/Tensor cores working will use more bandwith then the 2080 Ti, because with RTX turned on I think it's actually possible for the 3080 Ti to be twice as fast as the 2080 Ti...

What do you guys think? Should I worry about this?
 

MattS

Posts: 666   +180
TechSpot Elite
To put you in perspective, an RTX 2080 TI approximately utilizes 60% of a pcie 3.0 x16 slots bandwidth.

Next gen for your motherboard/setup wont be an issue. Maybe it will be an issue 3-4 years down the line however PCIE 3.0 x16 is still pretty darn good, so you nothing to worry about yet.
 
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To put you in perspective, an RTX 2080 TI approximately utilizes 60% of a pcie 3.0 x16 slots bandwidth.

Next gen for your motherboard/setup wont be an issue. Maybe it will be an issue 3-4 years down the line however PCIE 3.0 x16 is still pretty darn good, so you nothing to worry about yet.
Thank you!