Stress test

The stress test pushes your CPU, GPU, or VRAM to maximum load for an extended period. Unlike the performance benchmark, which measures speed, the stress test measures stability: whether your hardware can sustain peak performance without overheating, throttling, or crashing.

When to stress test

Stress testing pushes hardware to its limits and contributes to wear and tear. Use it when you have a specific reason. Examples are validating a new build or overclocks, checking used hardware before purchase, and diagnosing intermittent crashes that only appear under heavy load.

Selecting devices to stress

The stress test presents a hierarchical device tree that shows all compatible hardware in your system. You can select any combination of:

CPU Stress: sustains all processor cores at 100% usage. This exposes instability from inadequate cooling, insufficient power delivery, or aggressive overclocks
GPU Stress: runs an FMA-intensive compute shader that saturates shader cores, memory bandwidth, and power delivery
VRAM Stress: cycles through five distinct bit patterns across the full device-local VRAM allocation to detect stuck bits, coupling faults, and address errors

If your system has multiple GPUs, each appears as a separate branch in the tree with its own GPU Stress and VRAM Stress options. Select one, several, or all devices depending on what you want to validate.

Duration

The stress test duration is configurable from 1 minute to 8 hours.

Start short, and increase the duration only if you need to. A few minutes is enough to catch most instability from overclocks or cooling problems. If that passes and you want more confidence, extend to 15–30 minutes. Longer runs of several hours are useful for used hardware validation, or for diagnosing intermittent problems. Sustained maximum load does contribute to component wear.

Sequential vs. parallel execution

The stress test supports two execution modes.

Sequential (default)

Sequential mode tests one device at a time. If you select CPU, GPU, and VRAM, Novabench stresses the CPU first, then the GPU, then the VRAM. Each device runs for the full configured duration.

Sequential mode isolates each component. This makes it easier to identify which device has a stability problem. This mode is available on all plans.

Parallel (Pro)

Parallel mode stresses all selected devices simultaneously. This creates a worst-case power and thermal load. That is useful for testing system-level stability: power supply capacity, VRM headroom, overall cooling, and system-wide thermal throttling.

Parallel mode requires Pro or higher.

Note

GPU Stress and VRAM Stress cannot run in parallel on the same GPU because both operations compete for the same physical hardware.

Before you start

When you launch a stress test for the first time, Novabench shows a caution notice. The notice reminds you that stress testing deliberately pushes hardware to its limits. Before you run extended tests, make sure that your system has adequate cooling. This matters especially on laptops or passively cooled systems.

This notice appears once. It does not appear again on later runs.

During the test

While the stress test runs, a full-screen progress view shows:

Current device: the component under stress (in sequential mode)
Time remaining: countdown for the current device and overall test
Component progress: in sequential mode, shows "X of Y" to indicate how many devices are complete

You can cancel the stress test at any time. If a device fails (crashes, triggers a driver reset, or encounters an error), Novabench records the failure point and moves to the next device (sequential) or stops (parallel).

Reading your results

After the stress test completes (or is cancelled), the results screen shows a summary for each tested device.

Pass or fail

Each device receives a Pass or Fail verdict:

Pass: the device completed the full duration without errors or driver resets
Fail: the device encountered a problem before the duration expired. The results show the failure timestamp (for example, "Fail @ 2m 30s"). This indicates how long the device ran before it failed.

An overall pass/fail indicator at the top summarizes whether all devices passed.

Per-device metrics

For each device, the results show:

Metric	Description
Max temperature	Highest temperature reading during the stress test (°C)
Max power	Peak power draw during the test (watts)
Max frequency	Highest clock speed recorded during the test (MHz)
Min frequency	Lowest clock speed after the peak, which indicates throttle depth (MHz)
Throttle time	How long the device spent at reduced frequency after throttling began
Duration	Total time under stress (full duration, or partial if the device failed)

Understanding throttle behavior

To calculate throttle time, Novabench finds the peak frequency during the test, then measures how much the frequency dropped afterward. A large gap between max frequency and min frequency, combined with significant throttle time, indicates that the device could not sustain its peak performance.

For example, a CPU that reaches 5,000 MHz but drops to 4,200 MHz after 30 seconds of sustained load is thermally throttling. Better cooling (better paste, additional fans, or a different cooler) reduces throttle time and maintains higher sustained frequencies.

Sensor charts (Plus)

On Plus and above, the results include time-series charts for temperature and frequency throughout the stress test.

Sequential mode: each component gets its own color-coded region on the chart. You can see exactly when each device was tested, and how temperatures and frequencies changed
Parallel mode: all sensor data appears on a single merged chart, since all devices run simultaneously

Sensor charts show thermal ramp-up patterns, throttle points, and cooling recovery between sequential tests.

Pro Tip

Look for a temperature plateau in the sensor chart. If the temperature still climbs when the test ends, a longer duration gives a more complete picture of thermal behavior. If the temperature plateaus quickly, your cooling handles the load well.

Results history

Novabench saves past stress test results in a sortable, filterable grid. Each row shows the date, devices tested, pass rate, duration, and peak temperature. You can click any row to view the full results for that test.

Advanced filtering (by device type, pass/fail status, date range, temperature thresholds) requires Plus or above.

Feature availability by plan

Feature	Free	Plus	Pro
CPU, GPU, and VRAM stress testing	Yes	Yes	Yes
Sequential execution	Yes	Yes	Yes
Sensor charts (temperature, frequency)		Yes	Yes
Results grid with advanced filtering		Yes	Yes
Account sync		Yes	Yes
Result tagging (serial, hostname, custom tags)		Yes	Yes
Parallel execution			Yes

CPU benchmark: measure CPU performance under controlled workloads
GPU benchmark: measure GPU rendering and compute performance
Sensor monitoring: track temperature, power, and clock speeds over time
Understanding your scores: how benchmark scores work and what they mean
Troubleshooting: common issues and tips for reliable results