9970X crashes Corona on render finish and laggy IR

Corona Corona for 3ds Max Help Required
1

Hi all,

We’ve got a new workstation in the studio and are running into a few issues with Corona, specifically:

  • Quite often the whole PC is restarted when (or just before) the render is finished. It happens right when the render hits 100% and before it starts to save the render output. It doesn’t seem to matter where the files are saved (different drives, network storage, sometimes it happens even when the render output save is disabled). When working in Max it seems fine and the render can be stopped ok
  • A big lag after a render is finished. This seems to essentially freeze Max for a minute or more, taking even longer on larger scenes. Compared to other workstations we have this seems to be a lot longer than it should be (on same scenes). Rest of the PC seems unnaffected though, but sometimes this freezes other running instances of 3ds Max
  • IR render speed is fast but very laggy until at least 8 threads are removed from the compute. Rest of the PC works ok but Max, IR, Mat editor is so slow that it’s almost unusable. Creating a new material takes dozens of seconds for example. Once the threads are removed it gets better but it’s not ideal

It only happens in Corona, Vray and FStorm are running well. All the benchmarks etc are running well also and generally speaking everything else seems to be running without issues. Machine has all the latest Win updates and BIOS/drivers.

Windows 11 Pro, 3ds Max 2026, Corona 13 Hotfix 2

AMD Ryzen Threadripper 9970X
ASUS WS TRX50-Sage WIFI
2X Palit GeForce RTX 5090 GameRock, 32GB
256GB Micron/Crucial DDR5 5600MHz (4X64GB)
two SSDs and a large HDD
some fans etc (no liquid)

Please help.

Thanks!

All drivers ar

2

Are you using some kind of denoising? It can stress the PC by A LOT, more than just rendering. If the freezes/crashes occur due to denoising, you could make sure that:

  • the CPU is not overheating
  • other components are not overheating (e.g. VRMs)
  • you are not using any overclocking, just the stock settings

You should also make sure your BIOS and chipset driver are updated to the newest available versions.

3

No denoising is happening, all temperatures are well within the limit.

All clocks are standard, in fact running slightly lower (~90%), chipset drivers and BIOS are all up to date

4

Software like Corona or 3ds Max cannot reboot a PC, it has to be a hardware or driver problem. Can you check if the same thing happens with just 1 RAM stick installed, or 2?

5

Hi Maru,

We are exploring hardware/driver issues, but it’s only happening in Corona.

It actually happened just now, PC was rendering for about 2.5hrs without issues and as soon as I went to save the CXR from VFB it crashed. I got as far as clicking Save in the save dialog, then the whole PC died.

6

What exactly do you mean by “PC died”? Did it fully shut down? Rebooted?

7

Hi Maru,

It shut down for about a second or two, then rebooted. It’s a weird one, I know!

8

This is definitely some kind of hardware/driver problem. Is there anything in the Windows Event Viewer?

9

Nothing conclusive, we’re swapping the power supply and/or GPUs tomorrow and see if any of that helps. I am hoping the power supply is just faulty and doesn’t like Corona, but we will see. It’s such a weird problem to have that it’s hard to figure out

10

In my experience it almost memory related, timings, speed, latency and 10000+ other memory parameters that you can change..
Try lowering speeds or increasing voltage slightly

11

Try activeshade mode with arnold and see if also triggers the crash.

12

Agree, it’s almost always RAM. Run memory diagnostics/memtest overnight and it’ll probably show issues.

13

It looks like this was a faulty power supply, which was crashing the pc on this one very specific scenario. Swapped and so far it’s been ok!

14

Great to hear that the source of the problem has most likely been identified!