3080 at x8 Benchmarks anywhere?

[PineyCreek]

Perhaps a curious question, and it's doubtful I'll try getting a new GPU before the end of the current dumpster fire that is this year, but has anyone seen (or tested personally) benchmarks of the 3k series cards when they're limited to 8 PCI-E lanes?  I know the CPU bottlenecking question has been asked to death as well as the PCI-E 3.0 vs 4.0 question...my question is specifically in regards to x8 vs. x16 (though I suppose PCI-E 3 vs. 4 might make a difference there as well).

 

I'm curious if x8 would severely hamper the cards.  I'm thinking I would build a new system in the not terribly distant future, but was also considering getting a 3k card in my current system while leaving the current card in place (primarily for BOINC and F@H-type work)...but I admit I'd rather not kill my gaming performance if I can help it.  The GPU config with my CPU/chipset/motherboard will cut the slots to x8/x8 if both are populated.

 

If the performance cut would be severe, I was also thinking of grabbing another 1080Ti off ebay for about $300 less than a 3080 (again, for BOINC/F@H).

[WereCatf]

23 minutes ago, PineyCreek said:

but was also considering getting a 3k card in my current system while leaving the current card in place (primarily for BOINC and F@H-type work)...but I admit I'd rather not kill my gaming performance if I can help it.  The GPU config with my CPU/chipset/motherboard will cut the slots to x8/x8 if both are populated.

You could just as well check how much of a difference running your current GPU in an x1 - config would reduce BOINC/F@H - performance. It is in many ways similar to Bitcoin etc. workloads and those do not see a drop in performance even when the GPU is running in a x1 - config, so I don't really see why BOINC/F@H would, but this would leave the 16 lanes free for the 3000 - series GPU.

[BobVonBob]

No solid numbers on PCIe 4.0 x16 vs x8 to my knowledge, but based on the difference between PCIe 3.0 and 4.0 I wouldn't expect any performance loss until you drop down to 3.0 x8 or 4.0 x4, since that already had a small performance dip with the 2080 Ti.

 

Tests by Kitguru.

https://www.kitguru.net/components/graphic-cards/dominic-moass/nvidia-rtx-3080-pcie-4-0-vs-3-0-scaling-analysis/

[PineyCreek]

On 9/17/2020 at 10:18 PM, BobVonBob said:

No solid numbers on PCIe 4.0 x16 vs x8 to my knowledge, but based on the difference between PCIe 3.0 and 4.0 I wouldn't expect any performance loss until you drop down to 3.0 x8 or 4.0 x4, since that already had a small performance dip with the 2080 Ti.

 

Tests by Kitguru.

https://www.kitguru.net/components/graphic-cards/dominic-moass/nvidia-rtx-3080-pcie-4-0-vs-3-0-scaling-analysis/

Aye, well, that's the situation I would be in if I did so and put it in the old system...3080 as main, 1080Ti as secondary...but on X370 that would go to X8 PCI-E 3.0.  Probably wouldn't hurt the 1080Ti at all, but I'm thinking it might gimp the 3080 potentially.

Though, between supply, the potential capacitor issue, and nvidia's own tendency to issue minute downgrades/upgrades as completely different SKUs, it sounds like I'll be better off building a new system around the new video card when I actually buy.

Maybe I'll just grab another 1080Ti off ebay if I can get one at a reasonable price for a bit of extra F@H and BOINC crunch oomph.