RTX 4090 is very slow in rendering

[Jiri.Matys]

Hi,

I bought new RTX 4090 and its super slow in VRay GPU rendering in 3dsmax. It seems that it render few seconds and then stop for a few seconds and then render again and repeate. Its much slower then 3090 for some reason. But I tested fstorm and fstorm render without any problem. Is there something I can do?
Thank you.

It is RTX 4090 MSI Gaming Trio X.

Thank you for any help.

[vladimir_krastev]

Hi, thanks for posting. Have you tried the V-Ray Benchmark tool? Please test with it, do not forget to turn off everything else that could be loading the hardware before starting it and let us know how it goes.

[Jiri.Matys]

So I got 4133 in CUDA and 5239 in RTX. So this seems fine. But in 3ds max it is slow. Light Cache is terribly slow so I didnt see the render.

Is there any GPU scene I can test in 3ds max to see how it goes?

I got some nightly build but works fine with 3090.

[vladimir_krastev]

The Benchmark is actually a test scene. I guess you have something in your scene that is causing issues. Have you tested with Brute Force instead of Light Cache? If you want to you can send us the scene here or trough the support contact form for review. Please if you decide to use the support contact form include a link to this thread in your e-mail.

[Jiri.Matys]

Hmm, looks like I fixed it. Different driver and different vray version didnt help. After that I tried to install nvidia driver with clean install option enabled. And it looks its ok now, render very fast without problem. Hope it will be good tomorrow too

I use this solution when I buy 3090, but problem was different. But looks like this same procedure helps too. Its weird that everything working without any problem, only Vray need reinstall nvidia driver with clean install enabled.

[Jiri.Matys]

Hmm, I install newest VRay 6.1 on max 2024 and problem is back. Clean driver install doesnt help anymore (newest drivers). And switching to another renderer and back to vray gpu doesnt help either. When I reinstall graphics drivers, it help but only for the first rendering. When I stop it and start render again, it is terribly slow again. Dont know what I can try. Please can someone help to solve this problem.
Everything else is fast, only VRay GPU rendering is slow.

[Jiri.Matys]

So, expensive card is useless, great. I am pissed off, everything working normaly, only vray gpu is slower than my cpu. Fantastic product.

[Muhammed_Hamed]

Hey Jiri.Matys

There is a performance bug with the current Nvidia drivers, with GPUs connected to monitors. We are working closely with them on this topic
This behavior affects all GPU loads, including Vantage and V-Ray GPU and even video games. So this is not specific to Chaos products
How many cards do you have in your machine?
Is there a chance we have a remote session to check your setup?

Best,
Muhammed

[Muhammed_Hamed]

There are multiple things that trigger this behavior, a machine restart usually solves the issue until it gets triggered again. You will be able to verify if you take a look the GPU frequency using a monitoring application like GPUZ
The GPU will be stuck at around 700 Mhz

Best,
Muhammed

[seandunderdale]

For all the performance gains from a GPU, or multiple GPUs, Im forever worried about the time lost trouble shooting with drivers to try to get renders out. Its why I stay with CPU, even if its costs more money on average. With all my user errors tripping me up, I dont need Nvidia making things worse!

[Jiri.Matys]

I just tested another driver and it is the same. I have only one 4090.
I dont know if Vantage is ok or not, never work with it. But VRay benchmark works without any problem. When I restart, GPU rendering is still slow. Even Light Cache calculation is slow like working for a second and another second not.

[Jiri.Matys]

Hey Jiri.Matys

There is a performance bug with the current Nvidia drivers, with GPUs connected to monitors. We are working closely with them on this topic
This behavior affects all GPU loads, including Vantage and V-Ray GPU and even video games. So this is not specific to Chaos products
How many cards do you have in your machine?
Is there a chance we have a remote session to check your setup?

Best,
Muhammed

Yes, we can have a remote session, no problem.
I am also thinking about recording a video so you will see what it is doing.

[Jiri.Matys]

Hmm, this is really weird. Yesterday GPU rendering was super slow at the morning. I test it before I go to bed and it was fast and great. Dont know what happen but its ok so be it. But today I start computer and first render was slow and terrible. I didnt change a thing, dont know what is going on. And now last render was fast again. Really weird, maybe scene dependant, maybe how wel pc slept, really dont know. But there is something for sure. I bought expensive GPU because I thought after all those years GPU rendering in VRay is finally ok. But to be honest it is really terrible experience even in 2023 after all those years. I tried fstorm and it render without any problem, without any slowdowns, without any super looooong inicialization before each frame, just abdolutelly different experience. But I am using VRay for more then 10 years and I want to stick with it. But I am really disapointed.

[Muhammed_Hamed]

Sorry to hear about your experience!

This slowdown in performance is not scene dependent and is not specific to V-Ray GPU, it affects any GPU compute. There is nothing we can do on our side, other than waiting for Nvidia to release a fix

there are multiple things that could trigger or untrigger this behavior on video cards connected to monitors
The bug ID for this Nvidia problem is 4050208

About time to first pixel, this is on us we have multiple developers working on this at the moment.

Best,
Muhammed

[Jiri.Matys]

Sorry to hear about your experience!

This slowdown in performance is not scene dependent and is not specific to V-Ray GPU, it affects any GPU compute. There is nothing we can do on our side, other than waiting for Nvidia to release a fix

there are multiple things that could trigger or untrigger this behavior on video cards connected to monitors
The bug ID for this Nvidia problem is 4050208

About time to first pixel, this is on us we have multiple developers working on this at the moment.

Best,
Muhammed

But when I download and install some older nvidia driver result was the same. So is it driver dependant?