Dual 4080-S GTX-1080 performance

[𝑲]

This is an excellent program producing a great quality image for minimal input lag, but I wanted to see if I take some load off the GPU in demanding parts of the game.

I tried dual GPU to take the load of upscaling a 1440 resolution modded Skyrim with ENB to 2160. I am using 4080 Super and GTX 1080. Simply using the more powerful card provided better performance in all aspects (smoothness, input latency, frame rate), even in GPU usage. For example, a scene I can easily run upscaled at 60 FPS (no framegen) uses just under 60% of the main GPU, but when I send Lossless Scaling to do its work on the secondary GPU both cards go to about 80% and performance is much worse.

Do you think this is an issue with the extra time spent communicating between the cards? They are plugged into an Asrock x470 Taichi motherboard. Similarly with frame gen on (I only have a 60hz monitor, but I tested it at 30 and 40 real FPS), performance is much better with everything on the main GPU only (flow bar at 75%). Is there any use keeping the GTX 1080 plugged in or am I doing something wrong?

[DarkSkyline16]

I have no idea the deets on your setup but I love the fact you want to tinker and see what happens, thank you for your results.

All i can think of might be an issue is your X470 is PCI Gen 3 only (I think) so maybe going X570 might help?

[𝑲]

Originally posted by DarkSkyline16:

I have no idea the deets on your setup but I love the fact you want to tinker and see what happens, thank you for your results.

All i can think of might be an issue is your X470 is PCI Gen 3 only (I think) so maybe going X570 might help?

Thank you for the suggestion. I like to report on things like this even when it doesn't work out. Someone out there with a similar setup might be looking to see if anyone's tried it.
Looking into it more, it looks like when the second GPU is in action both GPUs go at PCI-E 8x. One GPU at a time is 16x. There is another slot lower down that is promising, but looking at the size of my 1080 and the bottom part of the case that covers the PSU I didn't try it. Maybe I could just fit it and I'll try that later.

Originally posted by https://www.tweaktown.com/reviews/8685/asrock-x470-taichi-amd-motherboard-review/index.html:

The PCI-E layout is simple; the top two x16 slots operate at x16/x0 or x8/x8 PCI-E 3.0 from the CPU. The PCI-E 2.0 x1 slots are linked to the PCH through a hub (which also provides for the WIFI/SATA). The last x16 slot is electrically x4 PCI-E 2.0 and shares all its bandwidth with the second M.2 slot.

[IceLancer]

Originally posted by 𝑲:

Originally posted by DarkSkyline16:

I have no idea the deets on your setup but I love the fact you want to tinker and see what happens, thank you for your results.

All i can think of might be an issue is your X470 is PCI Gen 3 only (I think) so maybe going X570 might help?

Thank you for the suggestion. I like to report on things like this even when it doesn't work out. Someone out there with a similar setup might be looking to see if anyone's tried it.
Looking into it more, it looks like when the second GPU is in action both GPUs go at PCI-E 8x. One GPU at a time is 16x. There is another slot lower down that is promising, but looking at the size of my 1080 and the bottom part of the case that covers the PSU I didn't try it. Maybe I could just fit it and I'll try that later.

Originally posted by https://www.tweaktown.com/reviews/8685/asrock-x470-taichi-amd-motherboard-review/index.html:

The PCI-E layout is simple; the top two x16 slots operate at x16/x0 or x8/x8 PCI-E 3.0 from the CPU. The PCI-E 2.0 x1 slots are linked to the PCH through a hub (which also provides for the WIFI/SATA). The last x16 slot is electrically x4 PCI-E 2.0 and shares all its bandwidth with the second M.2 slot.

This is quite the question. Can you change pci-ex lane speed in bios maybe? lower it down?
How about power distribution ? I could assume that you have adequate psu with enough rail power but i could be wrong? Is your Psu rated that high?

There might be some reddit posts explaining process in detail? I didnt dig deep into it.

[𝑲]

Reporting back I couldn't fit my 1080 into the lower PCI-E 2.0 16x slot to try. There are a couple of small PCI-E slots, but they would be worthless for this since they are 2.0 1x. If that 1080 could have fit, it would not share bandwidth with the main GPU, whereas it does in the higher PCI-E slot which is probably meant for SLI. Then my guess is that I would see better results in-game using Lossless Scaling, but another factor is that the 1080 would not contribute as much as it could due to the 2.0 speed of the chosen PCI-E slot.

Originally posted by IceLancer:

This is quite the question. Can you change pci-ex lane speed in bios maybe? lower it down?
How about power distribution ? I could assume that you have adequate psu with enough rail power but i could be wrong? Is your Psu rated that high?
There might be some reddit posts explaining process in detail? I didnt dig deep into it.

I'm pretty sure you can't change PCI-E speeds in BIOS. I looked in the manual to be sure and there was no way. My PSU is also nice, it is a platinum Seasonic 1000W... I got it in 2013 when my original Coolermaster 650W blew up in smoke a few weeks into my new build, and this was the only one they had to be the warranty replacement.

Anyway, I tried and it's not meant to be.

[IceLancer]

Originally posted by 𝑲:

This is an excellent program producing a great quality image for minimal input lag, but I wanted to see if I take some load off the GPU in demanding parts of the game.

I tried dual GPU to take the load of upscaling a 1440 resolution modded Skyrim with ENB to 2160. I am using 4080 Super and GTX 1080. Simply using the more powerful card provided better performance in all aspects (smoothness, input latency, frame rate), even in GPU usage. For example, a scene I can easily run upscaled at 60 FPS (no framegen) uses just under 60% of the main GPU, but when I send Lossless Scaling to do its work on the secondary GPU both cards go to about 80% and performance is much worse.

Do you think this is an issue with the extra time spent communicating between the cards? They are plugged into an Asrock x470 Taichi motherboard. Similarly with frame gen on (I only have a 60hz monitor, but I tested it at 30 and 40 real FPS), performance is much better with everything on the main GPU only (flow bar at 75%). Is there any use keeping the GTX 1080 plugged in or am I doing something wrong?

Wait a sec. I am bit confused what are you trying to achieve here?
Your monitor is 60hz and you wanna use LS to get more then 60 fps? (You said you can reach 60 without anything?)
But why would u wanna try to go above 60fps on a 60hz monitor? You gain nothing by it. You are most likely just undermining your self by attempting that?

Or did i not read what are you doing properly?

So what basically happens on a 60hz monitor is that you activate LS and you fps cap your game to 30 in order to activate LFGx2 and get 60.
But you are already at 60 without LFG , why doing it then?

[𝑲]

Originally posted by IceLancer:

Wait a sec. I am bit confused what are you trying to achieve here?
Your monitor is 60hz and you wanna use LS to get more then 60 fps? (You said you can reach 60 without anything?)
But why would u wanna try to go above 60fps on a 60hz monitor? You gain nothing by it. You are most likely just undermining your self by attempting that?

Or did i not read what are you doing properly?

So what basically happens on a 60hz monitor is that you activate LS and you fps cap your game to 30 in order to activate LFGx2 and get 60.
But you are already at 60 without LFG , why doing it then?

I only used frame generation to test it out, but it was not viable at capping at 30 (or 40) and filling in the rest. But I found that the small performance hit from upscaling from 1440 to 2160 can also be delegated to a secondary GPU. That's what I was after, sending the cost of upscaling to the GPU. In most cases I have solid 60 real FPS in-game, but in a few areas there is a lower frame rate when upscaled. My goal was to send the small cost of upscaling to a second GPU, which did seem to be working (at the same time as limiting the faster one). A distant second goal was to see if 30 real and 30 generated frames would work.

[IceLancer]

Originally posted by 𝑲:

Originally posted by IceLancer:

Wait a sec. I am bit confused what are you trying to achieve here?
Your monitor is 60hz and you wanna use LS to get more then 60 fps? (You said you can reach 60 without anything?)
But why would u wanna try to go above 60fps on a 60hz monitor? You gain nothing by it. You are most likely just undermining your self by attempting that?

Or did i not read what are you doing properly?

So what basically happens on a 60hz monitor is that you activate LS and you fps cap your game to 30 in order to activate LFGx2 and get 60.
But you are already at 60 without LFG , why doing it then?

I only used frame generation to test it out, but it was not viable at capping at 30 (or 40) and filling in the rest. But I found that the small performance hit from upscaling from 1440 to 2160 can also be delegated to a secondary GPU. That's what I was after, sending the cost of upscaling to the GPU. In most cases I have solid 60 real FPS in-game, but in a few areas there is a lower frame rate when upscaled. My goal was to send the small cost of upscaling to a second GPU, which did seem to be working (at the same time as limiting the faster one). A distant second goal was to see if 30 real and 30 generated frames would work.

I see, your attempt is much cleared now.
So maybe what happens is because now u are using 2nd weak gpu to upscale and frame gen at the same time? And that causes problem because gpu cant handle to upscale that ?

Have u tried only using it for FrameGen only?

Your solution might only be to wait until LS can separate upscaling on one gpu and framegen on another?

"Small performance upscaling from 1440 to 2160* But that upscaling small performance loss is done by 4080 , for 1080 that might be heavy task?

[𝑲]

Originally posted by IceLancer:

I see, your attempt is much cleared now.
So maybe what happens is because now u are using 2nd weak gpu to upscale and frame gen at the same time? And that causes problem because gpu cant handle to upscale that ?
Have u tried only using it for FrameGen only?

Yep, I tried frame gen only, upscaling only, and both. No good, unfortunately. Even just upscaling came with a huge performance cost, probably because it was limiting the main card. It's quicker to do everything with the single GPU. Not to worry, it was only that one game I was interested in helping. Thank you for your suggestions, but I've taken the second card out.

[IceLancer]

Originally posted by 𝑲:

Originally posted by IceLancer:

I see, your attempt is much cleared now.
So maybe what happens is because now u are using 2nd weak gpu to upscale and frame gen at the same time? And that causes problem because gpu cant handle to upscale that ?
Have u tried only using it for FrameGen only?

Yep, I tried frame gen only, upscaling only, and both. No good, unfortunately. Even just upscaling came with a huge performance cost, probably because it was limiting the main card. It's quicker to do everything with the single GPU. Not to worry, it was only that one game I was interested in helping. Thank you for your suggestions, but I've taken the second card out.

There seem to be more things involved to get it running properly. It doesnt seem to be just plug and play.
https://old.reddit.com/r/losslessscaling/comments/1ifs8jo/dual_gpu_on_lossless_scaling_feasible_or_just_a/

Quote reddit post
-----------------------------------------------------
"You need 2 cable on the same monitor but from one of each cards. 1st card run the game but second card capture and display the game. ( need to switch the input to the second card/cable on the monitor during game. And switch input on first card/cable when not playing or not using LS). The settings in LS are : -Prefered GPU : [Your second card]

-Display output : [Your second card too]

Works like a charm but dont forget to change input on the monitor each time playing otherwise LS just won't appear in game.

This is without SLI (cards can't communicate), with SLI idk if it works but im on my way to try!! So i could just use one cable and stop switching inputs!"
--------------------------------------------------------
They even have some gpu chart but i am lost in it. Its badly explained.
https://docs.google.com/spreadsheets/d/17MIWgCOcvIbezflIzTVX0yfMiPA_nQtHroeXB1eXEfI/edit?gid=1980287470#gid=1980287470


Its quite absurd and complete mess to be honest. In order to learn all one simply must sit couple days on Discord to find and learn. Everything is burred there
I dont think i am interested in doing it at all

I was playing psx and other 30 fps emulation with LS and i was more then happy with it on a single GPU . Ill stick to just that :)

P.S
Whats more above setup requires HDMI and DP or 2xHDMI. Which is a mess attempting to run HDMI at 2 or 4k. I dont think it can happen because of HDMI cap rate.
Could probably be done on some medium /entry monitors with hdmi input only.
Or try to find and buy if it exist 2x DP input splitter. I saw output split but not input and they are like 150$. Its just way too hassle