Warning Num Samples Per Thread Reduced To 32768 Rendering Might Be Slower Upd Page

“How much slower?”

In those cases, the reduction might be a symptom of a deeper configuration mismatch.

If your graphics driver is timing out (TDR), windows might force the renderer to restart, which causes this warning. You can increase the GPU timeout limit in the registry, though this is a more advanced fix. Is it Always Slower? “How much slower

Turn on (called Noise Threshold in Blender Cycles).

Displacement maps and high subdivision levels create massive amounts of "render-time geometry" that eat VRAM. Try lowering the Edge Length or using View-Dependent displacement. Is it Always Slower

In modern GPU rendering, the work of calculating light paths (samples) is divided among many parallel execution threads. Each thread is responsible for a certain number of samples before the results are combined into the final image. The "num samples per thread" parameter defines that batch size.

If you absolutely require massive sample counts for complex scientific renders or architectural interiors, look into . Try lowering the Edge Length or using View-Dependent

: Sometimes VRAM doesn't clear properly due to memory leaks. Restarting your 3D software or your PC can free up "stuck" memory.

Which are you using (Blender, Octane, Redshift)? What is your GPU model ? What is your current Total Sample count? Share public link

Next time you see it in your console, you'll know exactly what's happening under the hood and how to respond like a pro.

Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\GraphicsDrivers Create a DWORD (32-bit) value named . Set its value to 10 or 15 (seconds).