[SOLVED] Will PCIe 3.0 bottleneck something like an RTX 3080 Ti?

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K1llrzzZ

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Oct 27, 2013
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Hi!

I know this is a weird question to ask at this time, I won't be able to get a definite answer, since we know next to nothing about the RTX 3080 Ti, but I was just wondering. I usually buy a new GPU every generation of the Ti class(currently on the 2080 Ti), but I don't replace my CPU nearly as often since games are mostly bottlenecked by the GPU, especially at 4K where I play. However I did replace my ageing 4770K(it wasn't bottlenecking my 1080 Ti that bad at 4K, but I don't know if that would have been the case with the 2080 Ti) last november to an i9 9900K,. I'm not planning to replace my 9900K for at least a couple of years (maybe I will when the RTX 4080 Ti comes out), but since AMDs latest motherboards already support PCI 4.0, and my Z390 doesn't. I expect the next generation of GPUs from Nvidia to be PCI 4.0 cards, and I'm a bit nervous that PCI 3.0 will become a bottleneck at the high-end. TechPowerUp did an analysis of this with the RTX 2080 Ti:
https://www.techpowerup.com/review/nvidia-geforce-rtx-2080-ti-pci-express-scaling/7.html
What they found was that PCIe 3.0 8x was in fact a bottleneck here, tough the difference wasn't huge (2-3%). Does that mean, that in order for PCIe 3.0 16x to become a bottleneck, the GPU needs to be twice as fast as an RTX 2080 Ti or it doesn't work that way?

Thank you for the help in advance!
 
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Yes, it does mean that the GPU in theory needs to be twice as fast as an RTX 2080 Ti. PCIe 4.0 x8 is like PCIe 3.0 x16, so I don't think graphics cards are going to be limited by 3.0 much in the same way 3.0 cards weren't limited by 2.0 motherboards for a long while.

hftvhftv

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Yes, it does mean that the GPU in theory needs to be twice as fast as an RTX 2080 Ti. PCIe 4.0 x8 is like PCIe 3.0 x16, so I don't think graphics cards are going to be limited by 3.0 much in the same way 3.0 cards weren't limited by 2.0 motherboards for a long while.
 
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Oct 21, 2019
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No worries m8.
I bet you already saw videos on youtube where people tested GPUs woth PCI E x8 and x16. Did you recognize that most cards are running at the same speed with x8 and x16. A 2080ti is just slittly bottlenecked by PCI E x8 means x16 is more than enought. Current GPUs have already a realy small manufactorer size. Therefor i dont think that future generation in the next 5 to 6 years will improve much and i think PCI E 4.0 will be a long time usless for gaming GPUs because after all I said you have to know that programming is also improving and new engines are coming. Means more grafic details with less power. For me as a pc enthusiast I dont think that PCI E 4.0 is realy relevant...its just a money maker like 4k some years ago...no content but you should buy 4k if you trust the advertisments. Even PCIE 4.0 SSDs are for most people useless up to not necessary but nice to have.
 
Sep 2, 2020
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Yes, it does mean that the GPU in theory needs to be twice as fast as an RTX 2080 Ti. PCIe 4.0 x8 is like PCIe 3.0 x16, so I don't think graphics cards are going to be limited by 3.0 much in the same way 3.0 cards weren't limited by 2.0 motherboards for a long while.
Well, that aged pretty well.
 
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