CPU overheats and PC shuts down when rendering with 3ds Max

Issue:

When rendering with different render engines in 3ds Max (such as V-Ray or Arnold), the CPU will overheat after a few hours and the PC will shut down.

Environment:

3ds Max.
Arnold renderer.
Chaos Group V-Ray renderer

Causes:

Render engines such as Arnold or V-Ray are heavily multi-threaded and are designed to utilize every processor core of a CPU. During a long, complex rendering, if the CPU has inadequate cooling and is under heavy load, it may reach a threshold temperature and throttle back, impairing rendering speed, or generate enough heat to cause the PC to shut down.

Solution:

To address this issue:

Check System Requirements

Ensure the PC meets the minimum suggested system requirements: System requirements for Autodesk 3ds Max products.
Confirm that the PC components, especially the video card, or graphics processing unit (GPU) meet or exceed the 3ds Max Certified Hardware specs.

Check PC case, CPU and GPU cooling

Modern multi-core CPUs, such as the Intel i9 and AMD Ryzen Threadripper series, are extremely fast for rendering and simulation tasks, but also have demanding power and cooling requirements. Most 3rd-party PC vendors have taken these considerations into account and will pair CPUs and GPUs with the proper cooling hardware.

However, if building a new PC system from separate components, check the following:

Ensure adequate airflow through the PC case itself. Do not block the back of the case (pushing it up against a wall, drapes or so forth.)
Make sure the power supply is rated for the motherboard, CPU and GPU combination. Modern high-power PC components may require an 850-1200 watt power supply.
Check online reviews on reputable hardware websites for information on each major hardware component.
Make sure that CPU coolers (either air coolers or all-in-one (AIO) liquid-cooling systems are rated for the latest model of the CPU installed. For example, a CPU cooler rated as “good” for a 1st- or 2nd-generation AMD Ryzen Threadripper CPU may be completely inadequate to cool a 3rd-generation Ryzen CPU under prolonged use.
Do not overclock any CPU or GPU components. For maximum stability, keep voltages set to the defaults in the PC’s BIOS.
If local computer dealers are available, consult with them to get their recommendations for the system build, or see if they can build the system itself and guarantee its performance.