[SOLVED] How do I know if my RTX 3080 is being Bottlenecked by my CPU

[Bobo1458]

So I just got my RTX 3080 installed and I hopped on some of my favorite games to test out this beast of a GPU like: Borderlands 3, Forza Horizon 4, NFS Heat, Assassin's Creed Odyssey, and even Rainbow Six Siege. All to find out on ultra settings @ 1080p I was getting micro stuttering and FPS from 80-100 FPS on all of them. I've updated my drivers and now I'm at a cross roads. My CPU is a I7-8700k Overclocked to 4.7 ghz and it's liquid cooled.
Any help diagnosing this problem would be greatly appreciated!

 

[sizzling]

Try dropping down to 720p as a test. If you don’t see any noticeable improvement in FPS you very likely being limited by the cpu. As someone running a 3080 with a 1440p 144Hz monitor I could easily believe the cpu is limiting performance at 1080p.

 

[RTX 2080]

Full system specs please

 

[Bobo1458]

Full system specs please

RTX 3080 EVGA FTW
I7-8700k @4.7GHz
PSU 850w Corsair
Corsair Vengeance LPX 16GB (2x8GB) DDR4 DRAM 3000MHz
H100 Corsair Liquid Cooler
x3 Samsung SSD's - x2 500g x1 1 Terra
144 Hz 1080p Acer Monitor

 

[rolli59]

3080 is a 4k card so at 1080P the cpu is the limit.

 

[Bobo1458]

3080 is a 4k card so at 1080P the cpu is the limit.

So me getting lower framerates on 1080p is due to the CPU then?

 

[Bobo1458]

Try dropping down to 720p as a test. If you don’t see any noticeable improvement in FPS you very likely being limited by the cpu. As someone running a 3080 with a 1440p 144Hz monitor I could easily believe the cpu is limiting performance at 1080p.

Dropped it down to 720p on FH4 and didn't get any frames D: I hope it's not my CPU

 

[RTX 2080]

Dropped it down to 720p on FH4 and didn't get any frames D: I hope it's not my CPU

Yep, it certainly seems like it's your CPU.

The rest of your hardware is solid, but your CPU came out back in late 2017 and there have been a lot of improvements in CPU performance in the past several years.

When running at 1080p with a super-powerful graphics card, your CPU has to work extra hard to crank out all those pre-rendered frames that need to be sent to the GPU. If you don't have a powerful CPU, you'll be limited by your CPU when gaming at 1080p.

If you want higher frame rates than what you have now, you should upgrade your CPU. Since you have a 8700k, there is a good chance your motherboard is compatible with 9th generation CPUs. If you want to upgrade your CPU without replacing your motherboard, I'd recommend an i9-9900k.

 

[Bobo1458]

Yep, it certainly seems like it's your CPU.

The rest of your hardware is solid, but your CPU came out back in late 2017 and there have been a lot of improvements in CPU performance in the past several years.

When running at 1080p with a super-powerful graphics card, your CPU has to work extra hard to crank out all those pre-rendered frames that need to be sent to the GPU. If you don't have a powerful CPU, you'll be limited by your CPU when gaming at 1080p.

If you want higher frame rates than what you have now, you should upgrade your CPU. Since you have a 8700k, there is a good chance your motherboard is compatible with 9th generation CPUs. If you want to upgrade your CPU without replacing your motherboard, I'd recommend an i9-9900k.

Ahhhh . So I'm confused though, these two videos I just watched: (

View: https://www.youtube.com/watch?v=FR96m6KUSaM&t=14s&ab_channel=ForGamers)(https://www.youtube.com/watch?v=R034lSf7-5M&t=10s&ab_channel=54FPS

View: https://www.youtube.com/watch?v=R034lSf7-5M&t=10s&ab_channel=54FPS

show off my CPU with exceptional framerates 🙁

 

[RTX 2080]

Ahhhh. So I'm confused though, these two videos I just watched: (

View: https://www.youtube.com/watch?v=FR96m6KUSaM&t=14s&ab_channel=ForGamers)(https://www.youtube.com/watch?v=R034lSf7-5M&t=10s&ab_channel=54FPS

View: https://www.youtube.com/watch?v=R034lSf7-5M&t=10s&ab_channel=54FPS

show off my CPU with exceptional framerates 🙁

I looked at the first video, and it shows different games than the ones you mentioned I believe. Additionally, it shows all the CPUs overclocked to 5.0 GHz, whereas yours is running at 4.7 (according to you). It didn't seem mentioned in the video, so we don't know what RAM was being used in those tests (it might be faster than the 3000 MHz RAM you're using; RAM speed plays a part at high refresh rates as well).

 

[Bobo1458]

I looked at the first video, and it shows different games than the ones you mentioned I believe. Additionally, it shows all the CPUs overclocked to 5.0 GHz, whereas yours is running at 4.7 (according to you). It didn't seem mentioned in the video, so we don't know what RAM was being used in those tests (it might be faster than the 3000 MHz RAM you're using; RAM speed plays a part at high refresh rates as well).

Ok, very interesting. So my ram could potentially be limiting my FPS?

 

[RTX 2080]

Ok, very interesting. So my ram could potentially be limiting my FPS?

I should go a little more in depth to avoid misunderstandings:

CPUs feed GPUs pre-rendered frames, so if your CPU is too slow, it'll limit GPU's ability to do its job.

CPUs get their data in order to pre-render frames from RAM, so if you don't have enough RAM, have single-channel RAM instead of dual-channel RAM, or have RAM that is too slow, it can slow down your CPU from doing its job which in turn slows down your GPU. Make sense?

Now, Intel CPUs aren't very sensitive to RAM speed, but the higher frame rates you aim for, the more important stuff like RAM speed becomes. It is possible (but I don't know for sure) that maybe your 3000 MHz RAM speed is a contributing factor to the issues you have described, but I think that it's more likely CPU-related. I have 3000 MHz RAM as well and I have no trouble going over 120 fps, although I do have a i7-9700k overclocked to 5.1 GHz, so that's the difference.

 

[boju]

Well 80~100 fps with micro stuttering seems to be something else to me. True, 3080 is obvious to everyone is overpowering in 1080p, but, 8700k with current ram speed should be capable of more than what he's getting in those titles. It would be understandable in newer more cpu taxing games where frame prerendering allocations be stretched but even then, 8700k would still be worth at least 100~120fps by itself in many titles.

Cpu set's the fps cap, that's been said. I don't believe a faster card would reduce it. What was your previous gpu and frame rates?

 

[Bobo1458]

Well 80~100 fps with micro stuttering seems to be something else to me. True, 3080 is obvious to everyone is overpowering in 1080p, but, 8700k with current ram speed should be capable of more than what he's getting in those titles. It would be understandable in newer more cpu taxing games where frame prerendering allocations be stretched but even then, 8700k would still be worth at least 100~120fps by itself in many titles.

Cpu set's the fps cap, that's been said. I don't believe a faster card would reduce it. What was your previous gpu and frame rates?

That's what I was thinking and I didn't think my CPU was that bad. I had a 1080 Gigabyte Windforce before my 3080. It was weird because a couple months ago I started experiencing frame loss on Siege. I used to be able to get 144 fps constant with my 1080 at Ultra settings, then for some reason out of the blue I started only getting 90-100 fps constant at Ultra settings. My other games I thought played like a 1080 would play, with on average 90-100 fps on most games with high/ultra settings. I'm so confused as to what it might be. I even wiped my computer last night and played AC origins and odyssey and was getting 40-50 fps on highest settings. Doom was getting around 105-111 FPS.

Now, I am using pigtail connectors from my PSU to GPU, I have no clue if that might be causing the problem. x3 8 pin PCI E connectors from my PSU to GPU

 

[boju]

Previous issues remaining consistent, sort of. If temps are good and Windows is fresh install (not reset), it could be, or mixture of but not limited to, Geforce driver version, game update / settings, Geforce Experience if you use this to optimise, Windows build version - Gamebar and fullscreen optimisation, Windows / gpu power plans.

Are you using GE to optimise? This can optimise too much depending on quality slider in settings.

Fullscreen optimisation found under compatibility tab for game's exe. Disable to be in fullscreen rather than semi borderless. Some games may have issues with it.

What do you mean by pigtail? Multiple ends from the one output? Try 3 separate cables.

 

[--SID--]

RTX 3080 EVGA FTW
I7-8700k @4.7GHz
PSU 850w Corsair
Corsair Vengeance LPX 16GB (2x8GB) DDR4 DRAM 3000MHz
H100 Corsair Liquid Cooler
x3 Samsung SSD's - x2 500g x1 1 Terra
144 Hz 1080p Acer Monitor

What's your previous GPU?

 

[boju]

Theirs was Gtx1080

 

[Bobo1458]

Previous issues remaining consistent, sort of. If temps are good and Windows is fresh install (not reset), it could be, or mixture of but not limited to, Geforce driver version, game update / settings, Geforce Experience if you use this to optimise, Windows build version - Gamebar and fullscreen optimisation, Windows / gpu power plans.

Are you using GE to optimise? This can optimise too much depending on quality slider in settings.

Fullscreen optimisation found under compatibility tab for game's exe. Disable to be in fullscreen rather than semi borderless. Some games may have issues with it.

What do you mean by pigtail? Multiple ends from the one output? Try 3 separate cables.

So I am using GE to optimize, but I went and set my games to lowest settings and I’m still getting lower frames like it didn’t even make a difference.

Yeah pigtail like multiple ends from one output. I saw a JayzTwoCentz video saying that the type of power connector doesn’t make a substantial difference in frames. I saw this after I posted about the pigtails question 😅.
I’ll try the full screen idea!
I appreciate you trying to troubleshoot 🥴

 

[Bobo1458]

What's your previous GPU?

A GTX 1080 Gigabyte Windforce

 

[boju]

I use 1 8pin to 2x 8pin supplied by Corsair 750Hxi to power 1080Ti mainly for cable management. Been running it that way for quite a few years without issue. Gtx 3080's higher power use might be different though. Im not an psu guru to really know for sure. To be safe id try three separate to troubleshoot.

Instead of going lowest possible settings, try the opposite and go high as possible and work back from there. Add higher resolutions ingame using dsr in NvidiaCP or upping resolution scaling if game provides. Try different anti aliasing settings at 1080p or none at all if try dsr.

Geforce drivers, different versions can fix bugs or performance issues in a particular game warranting attention from the public but can also break stuff in others. Can be a circus between gpu driver, game dev and OS. It's usually smooth sailing really but there are some wonky waves. Not saying try every driver but perhaps try few versions since your card's first release till recent.

 

[Bobo1458]

I use 1 8pin to 2x 8pin supplied by Corsair 750Hxi to power 1080Ti mainly for cable management. Been running it that way for quite a few years without issue. Gtx 3080's higher power use might be different though. Im not an psu guru to really know for sure. To be safe id try three separate to troubleshoot.

Instead of going lowest possible settings, try the opposite and go high as possible and work back from there. Add higher resolutions ingame using dsr in NvidiaCP or upping resolution scaling if game provides. Try different anti aliasing settings at 1080p or none at all if try dsr.

Geforce drivers, different versions can fix bugs or performance issues in a particular game warranting attention from the public but can also break stuff in others. Can be a circus between gpu driver, game dev and OS. It's usually smooth sailing really but there are some wonky waves. Not saying try every driver but perhaps try few versions since your card's first release till recent.

Finally was able to troubleshoot and I think I found the solution to my problem! I had an 8 pin connector that had another 8 pin connector that was hanging off of it and I had that one plugged in, but found out that this cable was not giving the proper amount of power the GPU needed! So I'm ordering another 8 pin connector to test it out! I think this is the reason for the choppy frames, but going to run some tests again once I get my new connectors. Hopefully this is it!

 

[boju]

What model Corsair psu you got? Should have more than enough pcie cables. Don't use off the shelf pcie cables unless verified it's use is for your psu otherwise you run the risk of shorting your card. Psu industry don't follow pinout standard and cables designed for the particular unit redirect wires to the correct spots for the component. To be safe, only use cables supplied by the psu model or order specifically from the manufacturer.

 

[Bobo1458]

What model Corsair psu you got? Should have more than enough pcie cables. Don't use off the shelf pcie cables unless verified it's use is for your psu otherwise you run the risk of shorting your card. Psu industry don't follow pinout standard and cables designed for the particular unit redirect wires to the correct spots for the component. To be safe, only use cables supplied by the psu model or order specifically from the manufacturer.

I have a 850w Gold standard Corsair, but I lost all the other cables so I don't know where to buy more cables that will be okay for my PSU. I bought some off newegg here.

 

[boju]

Wouldn't be standard. Rmx, Txm, Ax, Hxi, be one of those. Im not sure about that cable. Corsair pinouts should be same across all their products, not sure. Best email them for replacement pcie cables for your psu model. Find out what model you have.

 

[Bobo1458]

Wouldn't be standard. Rmx, Txm, Ax, Hxi, be one of those. Im not sure about that cable. Corsair pinouts should be same across all their products, not sure. Best email them for replacement pcie cables for your psu model. Find out what model you have.

Ok, definitely. Do you think it would be too late to get pcie cables even though it's been over 3 years since I purchased the product?