PCIE 4 vs PCIE3Gen4?

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jarablue

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Will the 3000 series cards be a huge jump with pcie4?

I just built a 10700k system Z490-A prime board and have a 2060. Looking to get a 3080. Hope I didn't shoot myself in the foot if the perf increase is huge with pcie4.

What do you guys think?
 
PCIE3 gen4 isnt a thing. Its either PCIE3 or PCIE4.

I highly doubt there will be a jump considering going from PCIE3 x16 to x8 was a marginal loss in performance.
 
As stated, there is no such thing as pcie3 gen 4.

you may miss out on a couple percentage points of performanice in some edge cases. Unlikely to really notice it at all. We will all know for sure shortly though
 
It's be interesting to see 3300x/3600/3950x builds give up slot bandwidth advantage to 10600k/10900k oc'd frequency in game.
 
doubletake said:
vegeta535 said:
Currant cards

My favorite.
Click to expand...

They are quite tasty...

currantcard.jpg


Back on topic: I guess we will find out when the 30XX lineup hits and some thorough benchies are done on some Ryzen equipped boards sporting PCIE4... will be interesting to see if it really makes a difference. I'm guessing it'll help, but nothing dramatic, and probably only really noticeable gains at extreme resolution sporting mega textures.
 
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Video has tests of the performance impact on a RX5700XT at 4.0 and 3.0. The difference isn’t massive but it’s there and I would suspect it will be higher on more powerful cards.

 
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My understanding of it from AMD saying B550/x570 that PCI Express 4 is a direct link to a 7nm Ryzen CPU and does not even use the chipset for any GPU work , Also AMD is now using the 3800XT for driver lab testing according to there footnotes in 20.8.3

As for Steve's testing only the AMD system could show the different with a RX 5700XT as the Intel system would have to use the RX 5700XT also to compare the 3.0 x16 performance as the 2080Ti part never made scent to me in using it in the testing .
 
Well it might help with DirectStorage API where apparently gpu has direct access to ssd so 32gb/s vs 16gb/s at 16x :)
 
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rhansen5_99 said:
Well it might help with DirectStorage API where apparently gpu has direct access to ssd so 32gb/s vs 16gb/s at 16x :)
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This is a good point. Obviously, you would need a fast SSD like the upcoming 980 pro and games would need to support it (and Microsoft would need to release it), but this is actually a use case that I think is likely to happen and make a difference in the real world.

crazycrave said:
My understanding of it from AMD saying B550/x570 that PCI Express 4 is a direct link to a 7nm Ryzen CPU and does not even use the chipset for any GPU work , Also AMD is now using the 3800XT for driver lab testing according to there footnotes in 20.8.3
As for Steve's testing only the AMD system could show the different with a RX 5700XT as the Intel system would have to use the RX 5700XT also to compare the 3.0 x16 performance as the 2080Ti part never made scent to me in using it in the testing .
Click to expand...
Um.. that's the case for the 16x PEG slots in most recent Intel and AMD designs, PCIe gen 3 and 4. There are some PCIe slots coming off the chipset (for Intel and AMD) usually reserved for NVME and secondary PCIe slots, but the "main one" (16x) usually closest to the CPU is driven directly by the CPU.

I do wonder if being forced to use 8x PCIe 4.0 will hinder a 3000 series GPU very much in a direct storage game (whenever that happens) if someone has a motherboard where using the main PCIe 4.0 m.2 slots ends up splitting the 16x slot into 8x electrically. Not that uncommon to have motherboards that do this.
 
sethk said:
This is a good point. Obviously, you would need a fast SSD like the upcoming 980 pro and games would need to support it (and Microsoft would need to release it), but this is actually a use case that I think is likely to happen and make a difference in the real world.


Um.. that's the case for the 16x PEG slots in most recent Intel and AMD designs, PCIe gen 3 and 4. There are some PCIe slots coming off the chipset (for Intel and AMD) usually reserved for NVME and secondary PCIe slots, but the "main one" (16x) usually closest to the CPU is driven directly by the CPU.

I do wonder if being forced to use 8x PCIe 4.0 will hinder a 3000 series GPU very much in a direct storage game (whenever that happens) if someone has a motherboard where using the main PCIe 4.0 m.2 slots ends up splitting the 16x slot into 8x electrically. Not that uncommon to have motherboards that do this.
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AMD has direct CPU lanes to GPU and first NVME subsequent nvme are through chipset (x570 chipset has a x4 pcie 4.0 link, while b550 is x4 pcie 3.0, all Intel's are x4 3.0 equivalent links, regardless if you buy high or low end). Intel has16 lanes to GPU and all NVMEs are through chipset. For the first NVME any AMD b550/x570 allows the fastest speeds, for second nvme the x570 can run close to pcie 4.0 x4 depending on how much multiplexing the chipset needs to do.
All of this said, I highly doubt anyone would notice in 99% of situations, but there is a difference. How much of a difference is highly dependant on what you're doing. For gaming it is more noticeable at lower resolutions where more draw calls are made through the bus, and tapers off at higher resolutions where your more limited by drawing/processing than draw calls. It'll be interesting to see the difference it actually ends up making. My guess is around 0-2% at 4k... A bit more at 1440p and somewhere between 5-10% depending on game at 1080p. These are just my gut feelings with absolutely no guarantees or warranty ;).
 
rhansen5_99 said:
Well it might help with DirectStorage API where apparently gpu has direct access to ssd so 32gb/s vs 16gb/s at 16x :)
Click to expand...
From my understanding DirectStorage reduces the bandwidth needs.

Without DirectStorage PCI-E is hit twice (plus a couple times between CPU and RAM for compressed data). If the data is compressed, it has to traverse the PCI-E bus decompressed from RAM to GPU.
Code: 
SSD -- Compressed Data (via PCI-E) --> RAM --> CPU (Decompression) --> RAM -- Decompressed data (via PCI-E) --> GPU

With DirectStorage
Code: 
SSD -- Compressed Data (via PCI-E) --> GPU
 
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