Overclocking a CPU for Assetto Corsa

Billy Pilgrim

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Hi
I have an i7 4770k CPU which is I believe quite happy to be overclocked (and I have watercooling). I have overclocked it a little bit, not much.

My question is: will overclocking it more (to, say, 4.2 or 4.4Ghz) help me get more FPS in Assetto Corsa. Will it help especially in situations with a larger grid/more ai on track?

I'm getting a 1080 ti gfx card soon so the gfx card shouldn't be the bottleneck.

Anyone has any experience on this?
 

RasmusP

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Sorry for keeping it short but maybe it helps anyway :)
- download openhardwaremonitor
- set the GPU load to be drawn in the plot/graph
- play AC for 5 minutes or more and look if the GPU load is over 90% or not
- if not the fps limit is not the Graphicscard
- without fps limiter, vsync, gsync maximum or freesync maximum it's the CPU

CPU load is difficult to see the limit in load-numbers. More cores (or threads (hyperthreading)) gain fps but mostly it's single-thread-performance dependent. Deactivating cores for higher clock rates won't gain more fps! In example running 2 cores at 4.9 GHz instead of 4 cores at 4.4 GHz.

Overclocking with all cores/threads activated generates higher fps numbers though!

Can't really help you with how to overclock exactly. Just read a guide and study your bios and put the pieces together. You can't really fry modern Intel CPUs that easily. A good general start is to only touch the core voltage and the core multiplier. For Haswell and newer you have additional voltages and multiplier for the "Ring Bus".
The rest is mostly fine on default and is not altered automatically (other than core voltage with higher multipliers!).

You'll have to find a decent guide with recommended voltages for "safe 24/7" use for the Ring Bus and the core and set the multipliers accordingly (core is the important one, the ring bus has to stay in a certain range of the core though).

Finally the temperatures:
Everything below 80°C is "okay". Below 70°C is perfectly fine. You won't fry that chip though with temperature only. The PC will shut down at around 95° afaik without damage. It's not recommended to get close to the critical temp. 24/7 though!
Note: "I have watercooling" says nothing, sorry. A 1x 120 radiator AiO, combined with bad airflow in general will definitely be worse than any good air-cooler. Decent ones with optimized airflow can and will outperform air-cooling at a certain point of course :)

An example for a great and trustworthy, sadly German guide by the German OC guru "der8bauer":
http://extreme.pcgameshardware.de/o...swell-oc-guide-inkl-haswell-cpu-oc-liste.html

From that guide:
- VCCIN: Vcore + 0.4 V
- VCORE: 1.25 V
- RING: 1.15 V
- Ring Multi: "auto" or +/- 300 MHz Core multi

How I personally OC for quick success and while trusting the Hardware:
- set these voltages but don't touch multipliers yet (more volt = higher temps!)
- run a stress test and check Temps.! (I like to run the CPU stress from MSI Kombustor with one thread less than your CPU has)
- set the multipliers to values you'd like to test. I'd go with 4.2 GHz as most CPUs can do that easily!
- run the stress test and check temps again!
- try 4.7 GHz (that's from my experience. Some CPU can do it, some can not!)
- if not stable try 4.4 GHz to check the "bottom range".
- if stable check 4.5 and 4.6 afterwards
- always check temperatures after every change!
- settle with something that's stable. Making a non-stable multiplier stable is quite a journey with adjusting different things, check if it's working or not etc.

Read about fixed/offset/adaptive vcore modes!

Oh, do not touch the bclk! It's for experienced fine tuning only! My system gets completely unstable at anything other than default!

Hope that helps as a first step! Have fun with your PC! :)
 
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Richard Hessels

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If you run HD resolution and/or high graphic settings your GPU is the limiting factor.
200 mhz would hardly be more than 1 or 2 frames more.
As the whole system around the CPU is still more or less the same.
 

whitestar

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If you look at CPU performance reviews around the web people seem to agree that at 1080p high/ultra settings the CPU is still a factor, i.e. it will hold your GPU back if it's not fast enough. At 1440p things start to even out, and that's where the CPU becomes less of a factor in many games.

In other words – and with at high end graphics card – the following seems to be the norm:
@ 1080p you will see a clear difference in performance between the different CPUs in many games (depending on how CPU hungry they are, and AC is pretty CPU hungry I believe)
@ 1440p you will see a negligable difference in performance between the different CPUs in some games and still a significant difference in others
@ 2160p (4K) you will mostly not see any difference in performance between the different CPUs

So if you intend to play AC in 1080p then yes I expect you will see a significant gain, since AC seems to be a fairly CPU hungry game.

If you intend to play at 1440p or above, then you will probably not see a huge gain. But you'll just have to see. Follow Rasmus' procedure and test for yourself.

EDIT: Ooops wait now, if you're just overclocking with 200mhz then that won't give you much in terms of extra performance. I wouldn't even bother tbh.
 
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Jeremy Ford

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Overclocking another 200mhz is a 4.65% gain from 4.2 to 4.4, it's a marginal performance improvement I don't will think be to noticeable. Overclock to 4.4 and run AC with the Task Manager running. if your CPU is maxed at 100% then it's still a bottleneck.

My previous gaming PC was a 4770k with a 1080 Ti. More recently I've built a 8770k system with the Ti. The 4770k was consistently holding back the GPU with some stutter in VR racing titles, including AC. The 8770k eliminated the issue completely. I realise that doesn't directly answer your question, but it's useful to know from someone previously with the same build as the CPU will be holding back the full potential of that GPU.

As far as single screen gaming went , the 4770k was handling games just fine with the 1080 Ti at high frame rates with no stutter. That's not to say it still wasn't holding back the untapped potential of the Ti as it was if I compared the actual frame rates. 20 fps+, but when games are running at over 100 fps you can't tell.
 
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whitestar

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More recently I've built a 8700k system with the Ti.
I'm sure you meant that. :)
And yes, there seems to be a bit of stutter with older CPU regardless of their still high fps. I'm seeing it in GTA 5 and Far Cry 5 for example (with my old 2700K @ 4.4Ghz). I'm expecting my next upgrade (8700K) to fix that.
 

RasmusP

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Sorry but I'm getting triggered when I read things like "at UHD the gpu will limit" or something similar. Every game is different, especially Sims are different to AAA games.
Sure it's good to get opinions based on experience across many games but if someone wants to know what's the limiting factor with his current pc in a specific game:
You need facts and nothing else!

Checking gpu load is really easy and quickly done and also trustworthy in 99% of cases. (only when the game is badly coded or your PC has other problems its not)

CPU however is very different. I have fps drops with too many AI or too many apps while my I7 2600k is nowhere near full load. More like 40%. Spread perfectly about all cores but that's an optical lie because task manager etc are showing an average!
Then there is Witcher 3 for example where the CPU gets up to 80% and no fps drops happen, thanks to better multicore support.

So please all just check the gpu load in your games and if the gpu isn't at more than 90% load but you don't have a limiter etc active, it's the CPU.
RAM can help in some occasions but mainly it's just the CPU.

It really doesn't matter if some site or whatever tells you on which settings or resolutions the gpu is more important or after how many years this relationship will change. Watch the gpu load and you know what's the problem. Period.

Or if someone really wants proof, run process explorer, go into the details of a program and see the cpu load for the single threads.
The limit is 100% divided by amount of cores/threads so 12.5% for me with 8 threads.
The moment any thread hits more than 11.8%, the fps will drop.
(the peaks aren't visible and also more than this thread is running on the same core)

Now games with great multicore support will have 3 or more threads with similar load and when you unlimit the fps and let the game hit the CPU limit, they will all go up to 11% or higher.
Assetto corsa however looks more like this:
Thread 1: 12%
Thread 2: 7%
Thread 3: 5%
Not saying it's bad. It's extremely difficult to split something like a simulation into multiple threads and I think they hit the maximum for the limits of the ac engine.

Why do I get triggered about that?
Saw guys buying new graphics card, cpu or memory because they read things like in here and then became frustrated because their favorite games still ran like crap.
Get numbers, then decide based on clear and specific facts. Nothing else!
 

Jeremy Ford

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I'm sure you meant that. :)
And yes, there seems to be a bit of stutter with older CPU regardless of their still high fps. I'm seeing it in GTA 5 and Far Cry 5 for example (with my old 2700K @ 4.4Ghz). I'm expecting my next upgrade (8700K) to fix that.
Yeah, that's the one! I had 4"770" on the brain. The 4770k was a great CPU and to be fair still is very good runner for a 5 year old CPU, but it's fair to say the latest GPU tech is being held back by it. It's still remains a good match for a 1070 of below mind. And when the Volta based GPU's come this year that will really alienate those older CPU's.

Ryzen 2 should be dropping later this month whitestar so you'll have another option to think about. I did consider the Ryzen, but the first gen chips were a bit short of spectacular compared to the 8700k.
 

Billy Pilgrim

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Thanks a lots for all your replies. Great!
:)
I'm gonna start by installing openhardwaremonitor to see what the GPU load is like in AC.

I only use my PC for AC anyway. And I have three screens @5760x1080. I've got the 1080ti installed and running now and I'm getting 80 to 100 fps pretty much with a grid of 16 or 17 ai opponents. Running all setting on ultra :) . It's great, but I would be happy with another 5 or 10% of fps.
 

whitestar

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Ryzen 2 should be dropping later this month whitestar so you'll have another option to think about. I did consider the Ryzen, but the first gen chips were a bit short of spectacular compared to the 8700k.
Actually I took a gamble and just ordered the 8700K. Early reports on the Ryzen 2700X suggest it won't beat or even be as quick as the 8700K in games, and games is all I use my CPU for. So it was an easy choice really. :)
 

Billy Pilgrim

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i tried out using the Openhardwaremonitor, running AC for five minutes.

The graph showed that GPU load was a little under 90% most of the time with a few peaks up to practically 100%.The vast majority of the time it was a little under 90% though.
 

RasmusP

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i tried out using the Openhardwaremonitor, running AC for five minutes.

The graph showed that GPU load was a little under 90% most of the time with a few peaks up to practically 100%.The vast majority of the time it was a little under 90% though.
That means that the peaks will cause fps drops but while it's below 90% it's definitely CPU limited.
As it's not like for me at 1920x1080 and a 1070 which is only around 40%, 200-400 MHz higher on the CPU might give you enough boost to reach the maximum of the graphics card :)
Also a few percent are doable with overclocking the memory. Beware though: it's easy to just try a higher speed (I could easily just switch from 1333 MHz to 1600 MHz) but when it fails, not even the bios will load and it will depend on your motherboard what you need to do.
For me it's 3x trying to start and my bios will reset, for many other motherboards it means opening the case and either pushing a button or putting a jumper on some pins for 30 seconds.

I would suggest you do what I wrote above and checkout the limit of your CPU. Be prepared for some bluescreens so don't work on something for hours without saving until your CPU runs stable for a week or something!

I wish you good luck and success. It's not as complicated as you'd think. It just takes some time to get the hook of it :)
 
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Insert Coin

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If you want a quick test to see if your overclock is stable: run Intel Burn Test on setting High for 10 minutes and while keeping an eye on the CPU temperature. As a final test run it for an hour (my 2600k gave a blue screen at 4.6 GHz only after 40 minutes..., it runs flawlessly at 4.5 GHz).
 

RasmusP

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If you want a quick test to see if your overclock is stable: run Intel Burn Test on setting High for 10 minutes and while keeping an eye on the CPU temperature. As a final test run it for an hour (my 2600k gave a blue screen at 4.6 GHz only after 40 minutes..., it runs flawlessly at 4.5 GHz).
True! Although Intel burn let's my Hardware monitoring freeze so I don't really see the temperature changes. Also no game ever reaches the temps of Intel burn, not even video rendering does!
Little addition: I use offset vcore so my vcore is a little lower compared to stock settings while being in the lower frequencies. My main problem was to get bluescreens when the state changed. So starting an application, quitting applications etc. As long as it stayed at maximum frequency everything was fine.

Newer motherboards might have some better vcore option which only enables custom vcore when going higher than default frequencies!
 
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I have a pretty ancient 3930k which will still OC to 4.4Ghz ( from 3.2/3.8 turbo, that is very noticeable ). In AC I never went anywhere near CPU limits even with a full field until I went to 7680x1440/crossfire, and that was a bit of a surprise.
 
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Hi guys, just thought I'd update this thread with my latest experience.

I upgraded my PC from a I7-7700 to a I9-9900K and the gain in AC is massive. Before I was lucky to get 45-80 fps and never able to get 89-90 fps most of the time with a full grid (20 AI). Now with my new setup it is impressive. At the start of a race I see a small fluctuation where the fps sometimes drops down to 80-84 fps, but that is mostly gone in the first lap. After that it's 89-90 fps all the way! I made a short video in Oculus Rift VR to show it:
My cpu is overclocked to 5.1 Ghz and I'm using Corsair H150i watercooling, which keeps the cpu well below 80 degrees Celsius. I see only 2 cpu threads being used by AC. My cpu doesn't seem to be very busy during gameplay, but my GTX 1080ti however is working at 90-98% full capacity. Just to show that cpu can really be a bottleneck.
 
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Andrew_WOT

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VR is more than double demand on CPU and requires the latest and greatest to keep up with 90 fps, dual screen rendering.
 

HugoB

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Hi guys, just thought I'd update this thread with my latest experience.

I upgraded my PC from a I7-7700 to a I9-9900K and the gain in AC is massive. Before I was lucky to get 45-80 fps and never able to get 89-90 fps most of the time with a full grid (20 AI). Now with my new setup it is impressive. At the start of a race I see a small fluctuation where the fps sometimes drops down to 80-84 fps, but that is mostly gone in the first lap. After that it's 89-90 fps all the way! I made a short video in Oculus Rift VR to show it:
My cpu is overclocked to 5.1 Ghz and I'm using Corsair H150i watercooling, which keeps the cpu well below 80 degrees Celsius. I see only 2 cpu threads being used by AC. My cpu doesn't seem to be very busy during gameplay, but my GTX 1080ti however is working at 90-98% full capacity. Just to show that cpu can really be a bottleneck.
I'm using an 6850K which has a boost of 4Ghz on one core. This is definitely limiting my AI capabilities. GPU is Titan XP, RAM is 32Gb 3200 CL14, SSD Samsung 850. I can run around 12 AI with 90fps in VR but I need to set most everything to low or off. Running a full grid of 23 is impossible, unless I want to keep it locked at 45fps with ASW. Do you think I can run a full frid with the 9900K together with my Titan XP? What settings do you use in AC? Shadows, reflections, PP, mirrors, smoke etc, and SS? Sol?

Thanks!
 
Feb 23, 2018
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I'm using an 6850K which has a boost of 4Ghz on one core. This is definitely limiting my AI capabilities. GPU is Titan XP, RAM is 32Gb 3200 CL14, SSD Samsung 850. I can run around 12 AI with 90fps in VR but I need to set most everything to low or off. Running a full grid of 23 is impossible, unless I want to keep it locked at 45fps with ASW. Do you think I can run a full frid with the 9900K together with my Titan XP? What settings do you use in AC? Shadows, reflections, PP, mirrors, smoke etc, and SS? Sol?

Thanks!
These are my settings in CM. I'm using SOL 1.1 alpha 7 and Light Shaders Patch preview 63.
Knipsel.JPG

This is a VR recording @ 89-90 fps almost constant with a full grid of Formula Hybrids 2018:


So yes, you will definitely benefit from a i9-9900K.
 

HugoB

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These are my settings in CM. I'm using SOL 1.1 alpha 7 and Light Shaders Patch preview 63.
View attachment 297142

This is a VR recording @ 89-90 fps almost constant with a full grid of Formula Hybrids 2018:


So yes, you will definitely benefit from a i9-9900K.
Holy crap that's awesome! You are using my 'solo racing' settings with a full grid!! :confused: If I'd choose those settings (especially with Sol enabled) with a full grid I wouldn't even be able to get 45fps..

That 9900K is mighty powerful indeed.

What GPU are you using? And what RAM? SSD?

Edit: never mind, found the answer in another thread you posted, 1080Ti right? Did you overclock it? Should be about the same as my Titan XP right? There might be hope for me! :rolleyes:

Oh, and in the youtube video, you mean a full grid of AI or is it online?
 
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