I have done a bit of research on the Zwift graphics engine and nothing comes up.
Just out of pure interested, perhaps someone at Zwift can post what the native fps game rate range actually is.
With a whole new set-up using the Ryzen 9 7950X, 64Gb of DDR5 RAM and the RTX5070 the game runs at 4K-2160p 120fps no problem but occasionally the frame rate drops when it gets busy but the GPU and CPU usage doesn’t change and is well within the limits so it points to Zwift maxing out. Yet to see the GPU go above 70%, most of the time its 30 to 40% with the frame rate locked at 120, GPU is 3 to 5%, seen it go 8% tops.
Looks to me like the Nvidia variable frame rate kicks in when 120fps is simply no there.
I wouldn’t bother posting that the new rig cannot keep up with Zwift, there are multiple ways to track the performance and its not maxing out anywhere. I moved from a 10 year old GTX750Ti so I know what serious bottlenecking looks like, the GPU was at 100% the whole time trying to put up 1080p 30fps and the GPU was at 40%.and it just crashed and burned on the New York underground.
I don’t want to get into an argument about my set-up, the graphics are amazing if you are prepared to get a decent set-up, the lighting in particular all changes on the rider, you are literally seeing things not present unless you have 4K.
You say a lot about GPU utilisation, but it’s well-known that single core CPU utilisation is usually the bottleneck for Zwift. What is the busiest Individual CPU core’s utilisation at these times when the frame rate drops?
There is no native FPS range on PC (or Mac). It is uncapped unless v-sync is enabled, then it will try to sync with the display refresh rate. I’m not Zwift. I run https://trainerdx.com formerly known as Zwiftalizer. I’ve seen a lot of log files over 10 years.
Thanks that is useful information. The Ryzen 9 7950X is more of a Workstation CPU so its not listed, but after running it on Zwift the results look like 120fps 99% of the time and the average would be like 118fps with the very occasional momentary dip to like 94fps. Probably not worth throwing 3 or 4 times the cash at it to make up the shortfall. I got the PC at a very good price based on what DDR5 6000 Ram costs now, not to mention the supply of new GPU’s is about to go off a cliff so you currently want a set-up thats going to last you a few years at least.
120 FPS 99% of the time tracks with what I see in the following search results for a medium size crowd - where the orange bar is the other 1% which dips below 120 in all the results.
Single core performance is definitely the bottleneck. While there isn’t an RTX 5070 in the results, the GPUs in the results also average 120 FPS or higher, except for the 4080 in Makuri - the world with the higest demand on GPU.
Your system is a beast and yeah I agree not worth putting more money into it, and for other stuff high number of cores and DDR5 makes total sense. But for anyone else reading who might be building a PC just for Zwift, 16 cores is not necessary. Most cores will be idle. A 12th Gen Core i3-12100 with 4 cores is sufficient.
Really great point about ram costs going up and supply of gaming GPUs going off a cliff. I read NVIDIA is cutting production of 50xx series GPUs by 30%-40%. Your old GTX750Ti might be worth more now
Thanks for the info. Yes there comes a point that spending more on the PC is a waste of time and you are better off getting an LG C5 48” OLED instead Stunning visuals so good that the sudden 19% decline in the NY underground actually induces the same feeling as an elevator does going down to your body.
On that last point, I’d just buy whatever beast of a machine that you can justify/afford (even if it is seemingly overkill) because in 3-6 months time the prices of RAM or GPUs might be even more stupidly high with the AI nonsense.
My RAM is even worse, it’s ECC ram (for servers/workstations) and the prices are astronomical. If I had purchased my intended 2x 192GB 6 months ago and not used it, I could have resold it at a massive profit. It’s a terrible situation for everyone.
If I had purchased my intended 2x 192GB 6 months ago and not used it, I could have resold it at a massive profit. It’s a terrible situation for everyone.