Question about CPUs and performance
SnowSultan
Posts: 3,648
I'm getting hit with a million Google News stories about new CPUs and some have made me curious as to how my current system still holds up. I don't really feel like mine is underperforming (especially with the new 2080ti), but it's been quite a while since I bought a new CPU and motherboard and some of these articles are saying that there are performance improvements to 3D rendering (I assume with simulations and other mesh calculations, not with actual rendering speed) with the newer Ryzen chipsets and such.
Here is my current CPU and motherboard:
CPU: Intel Core i7-5820K 3.3 Ghz 6-Core Processor
Motherboard: MSI X99A SLI Krait Edition ATX LGA2011-3
When I compare the very basic specs of that processor to some new ones, they don't sound that different (6 cores, still in the recommended 3-4 Ghz range), so I have doubts whether it would be worth the trouble to get a new CPU and motherboard for a slight increase in performance. Probably safe to say that the 20-core ones would be a noticable improvement, but it would have to be a titanic improvement for $1000+. If you have any recommedations, could you share your thoughts? Thanks very much in advance.
Daz 3D is part of 
Connect
DAZ Productions, Inc.
7533 S Center View Ct #4664
West Jordan, UT 84084
Licensing Agreement | Terms of Service | Privacy Policy | EULA
© 2025 Daz Productions Inc. All Rights Reserved.
Comments
Threadripper is current top CPU to render large scenes and denoising will speed up render time. Otherwise your current CPU is capable enough to render with 2080ti.
Yes, I did mention above that my system is performing well with the 2080ti and this CPU. I'm interested in hearing opinions on possible performance increases with newer CPUs compared to my current one.
The CPU doesn't matter. A single threaded app like Daz could actually suffer on a CPU with a larger number of slower cores. I upgraded from an AMD Phenom II X6 to a Threadripper 1950X, the baddest of the bad at the time, and saw virtually no improvement. On the other hand, a parallel task like compiling the Linux kernel went from twelve minutes down to 27 seconds.
The truth of the matter is that many applications, or tasks within an application, are still single threaded. In such cases, more cores doesn't do much good, and all those additional cores spend a lot of time executing idle instructions. Benefits that come from new instruction sets, the number of instructions executed per clock pulse, or clock frequency are another story.
The biggest thing that would benefit from multiple cores is CPU rendering, but for rendering in Iray on GPU, it probably doesn't matter all that much.
- Greg
That's very interesting, thank you for explaining it. I would have thought that after all these years, that processor would be holding back the potential of my other more updated and recent hardware. Would an updated CPU help other programs like Photoshop or After Effects, or do games and more programming-related calculations benefit the most from one?
I have the same CPU+motherboard and couple of months ago got the upgrade-flu, also thinking that the system is already 4 years old, but the flu was cured by replacing the 4GB GTX 960 with a 8GB RTX 2070 Super and increasing the RAM 32GB -> 64GB.
With the new GPU, the system doesn't give the impression of being the bottleneck, and as it is, it would still serve my needs for 2-3 years, but... Still I want to make a jump to a newer generation before the new components require W10
It is difficult to find information on how big of an effect would be realized by which upgrade, but I have previously used cpubenchmark as one source of comparative information - For now it looks like something like i9-10940X 3,3 GHz LGA2066 would be three times "faster" than i7-5820K, which is a lot less than I thought and since the upgrade (i9-10940X+WS X299 Sage) would cost close to $1700 (vat.incl) here in Finland, I'm going to wait until the fall or even next year, if something else comes up or the prices go down.
Going to the "dark side" is not an option, as having been involved with computers since -87, at times professionally, at times even betatesting HW, I have "learned" that going with Intel, gives better chances of the hardware not being the problem.
If I was feeling that the current rig was lagging, I could hunt down i7-6950X, which is listed at cpubenchmark as twice as "fast" and would give me 4 more cores, but twice as fast is not much...
If you consider a 6 core i7 as not being a recent upgrade please let up know when you buy one of these Ampere GPUs when they come out as I'm excited to her the 1st reports from actual DAZ users.
PS:
Just look up new CPUs & GPUs here:
https://www.passmark.com/
It was so easy to compare multiple CPUs / GPUs at one and then look up prices on them. It was key to me building a great desktop for under $700 (it helped a lot I didn't need a monitor).
I have an 8 core 16 thread Ryzen and I can say it made a huge difference compared to my 4 core 8 tthread i7 (it was 8 years old though).
I've been using a Threadripper 1950x since release. I have a 980ti.
In Iray, the 980ti is significantly quicker than the CPU ( about 40%). A scene in Iray taking 10 minutes on the 980ti would be somewhere around 15 on the CPU.
... In Blender, however, it is rare for the 980ti to be quicker, and is often significantly slower; take significantly to mean 20% at the minimum and often to mean only once so far has the GPU been faster. I haven't rendered in Studio for about two months now, with the exception of some comparrisons. I usually render with both as Cycles handles out of core rendering.
Moving to Blender has saved me thousands in cash (literally as since moving house I'd saved up for a Titan again). I will upgrade the card eventually, but I will also be upgrading the CPU.
Upgrading your CPU would improve peformance in Photoshop and Aftereffects. By how much? Depends on the CPU. Getting a new CPU in the same price range as the 5820k would get you probably about a 10% performance improvement. So if you do a lot of video editing or image editing as part of making money it might be worth considering an upgrade, shaving minutes off a video editing job could mean getting more work done per day. If this is just a hobby or only a small part of your work I'd leave it for a while.
Upgrading your CPU just for Daz Iray would not make any sense at all. Iray is far too GPU focused. Even if you intend to use the CPU to render with a GPU, the gains are marginal at best.
The only situation where upgrading CPU for Iray makes sense is if your scenes are so large that you cannot ever use a GPU. By going CPU you would only be restricted by system RAM, not VRAM. But to get even "OK" rendering speed, you would need to shell out several thousand dollars for big Threadrippers. I believe the $2000 Threadripper was about as fast as a GTX 1080, which isn't too bad. But that is comparing a $2000 CPU to a GPU that is now over 4 years old and is about to be two whole generations behind once Ampere releases. So 1080 level performance is not really that impressive as more and more cards can beat that. The 2060 can beat a 1080 easily at Iray today, so of course a 3060 will be even faster, and the 3050 (if it exists) would be around a 1080 level. That is how far GPU performance has gone in these years since 2016.
Alternatively, you could spend around $2000 for a Titan RTX, which offers 24GB of VRAM. Of course a CPU could have access to 64 or even 128GB of RAM if you install enough, but the Titan RTX would be several times faster as long as you can restrain yourself to stay under 24GB.
Updating the GPU might make other apps faster. If you render in other programs, like Blender, then it would be a big gain. And of course Daz still offers 3DL as a render option, a Threadripper would probably be a total beast for 3DL.
So ultimately it depends on what you use your computer for more, but if Iray is your main focus, I wouldn't bother. And like others said, the Daz app itself is single threaded, so only single core IPC and clock gains would help the app itself run better.
Thanks very much for the new information. Yeah I plan on sticking with Studio (tried Blender, it's powerful but more than I need and I still prefer using DAZ content natively), so that pretty much answers my question. I'd rather put that money towards another video card (maybe the 2080tis will fall in price a bit once the 3080s hit) than have to rebuild my entire system for a minor upgrade.
For my RTX 2080, I agree that the gains are marginal for the first few (eg, <= 3) CPU cores you allocate for rendering. After that, overall rendering performance takes and big hit,and the GPU was only utilized at 80%. I was a little surprised when I first saw this, but then I realized that it was probably because multiple CPU cores doing rendering takes away from the CPU's ability to schedule CUDA core rendering, resulting in an inablity to keep enough CUDA cores on the GPU busy and a significant drop in overall rendering performance.
After I saw that, I now prevent the CPU from doing any rendering at all.
Yeah I've disabled CPU rendering too and not run into any problems.
On a slightly OT subject but still regarding CPUs, can anyone give estimations on how they improve gaming? Can you reach 120hz on a AAA game with a 2080ti and high settings on a good monitor without also needing an i9-9900 or something similar? I can get 60hz at 1440p on ultra graphical settings with memory to spare on the 2080ti, but I don't have a monitor above 60hz to test how it would run at 120 or 144hz.
For gaming it depends on your resolution. As resolution goes up, you actually become more GPU bound, so the CPU is not holding you back as much. At 1440p, you will see smaller margins between the best best CPUs and yours than you would at 1080p.
You can still test with a 60 hz monitor, most GPU monitoring apps will report your frame rate unless you manually cap it with Vsync or a hard cap. So just make sure you are set to run at unlocked frame rates and you should get a decent idea. There will be some screen tearing because of this, but this is for testing purposes. This should tell you all you need to know.
I bought a 1440p monitor myself because the 4K monitors with Gysnc and higher than 60 Hz are still too expensive, and I wanted a 60+ experience. That and I really don't see a huge difference between 1440p and 4K at the screen size of a monitor. It is there, but I have to squint to really notice. My monitor is 144 Hz with Gsync support (not true Gsync, but it supports it,) and has wonderfully low input lag. That's good enough for me. My CPU is only a 4 core i5 4690K, and while it may bottleneck my 1080ti, it is not too severe. I can hit the 90-120 fps in a number of games at 1440p, though I have not been playing the big AAA games lately. The only monitor I would want to upgrade from this would be OLED when they start to become available and cheaper for monitors.
AMD has some solid stuff coming. I had originally planned on getting a 12 core Ryzen, but then I decided I don't really need that. Moving forward, both new consoles will have 8 core 16 thread Ryzens, and I believe that this will start to become a baseline soon. So when you do upgrade later on, I would start with that. But for now you are probably fine.
One of the better people to ask would be Steve at Hardware Unboxed. They made a dedicated video for the 5820k back in 2018. They found it to still be good enough that it didn't warrant an upgrade for gaming. Of course this was two years ago, and a lot of hardware and games have launched since then.
Thanks for that information, I just ran some uncapped benchmark tests now. Was able to get 89 fps average on Assassin's Creed Odyssey at 1440p at fairly high settings (in-game benchmark results, I didn't use additional outside software). I assume that the game being on a standard hard drive rather than an SSD could contribute to any performance hit (I put games there to separate them from 3D content, but I plan on getting another SSD for them), but I don't know what else I could do to improve on those numbers. The 2080ti eats any game for breakfast; even Red Dead Redemption 2 can be maxed out with 6GB RAM to spare. I guess that's why I thought the CPU could be the bottleneck. Thanks again for the helpful information so far.