How to Run the Volume Shader BM Benchmark (And Read Your Score)
The Volume Shader BM benchmark is a demanding GPU workload for measuring shader throughput. Here's how to run it, what your score means, and how to use it to compare cards and tune your system.
There are benchmarks that measure how a card plays a specific game, and then there are benchmarks that measure the card itself. Volume Shader BM belongs to the second category. It is a heavy, repeatable shader workload that pushes fill rate and compute throughput to their limits — the kind of test that separates a genuinely fast GPU from one that merely feels fast in easy scenes. In this guide you will learn how to run the Volume Shader BM benchmark, what the score actually represents, and how to use it to compare cards and tune your own system.
What Volume Shader BM measures
Volume Shader BM drives the GPU with a dense, sustained volume-rendering style workload. Volume rendering — used in scientific visualization, medical imaging, clouds, and smoke — is brutal because it forces the GPU to evaluate a stack of layers per pixel rather than a single surface. That makes it an excellent general stress test for two reasons:
- It uses the whole pipeline. Compute, fill rate, memory bandwidth, and shader units are all pushed simultaneously.
- It is deterministic. The same workload runs every time, so scores are directly comparable across cards, drivers, and settings.
Why determinism matters: A benchmark that generates a different scene each run produces different scores for reasons unrelated to performance. Volume Shader BM runs the same workload every time, so a higher score really does mean a faster card.
Step-by-step: run the Volume Shader BM benchmark
1. Prepare your system
A fair benchmark needs a quiet system. Before you run:
- Close browsers, launchers, recording software, and other games.
- Make sure the card is at its normal idle temperature (let it cool if you just gamed).
- Decide on your target resolution and keep it consistent across runs.
2. Open the benchmark
Navigate to the Volume Shader BM benchmark. The test runs entirely in your browser using the GPU's WebGL/WebGPU capabilities — no installation, no drivers to configure, no admin rights.
3. Run a warm-up pass first
The first run always scores a little low: the GPU boosts to its clocks, caches warm up, and drivers optimize on the fly. Run the benchmark once and discard that result. Then run it again for your real score.
4. Run it three times and take the median
Single runs vary. To get a trustworthy number:
Run 1: 11,240 (warm-up, discard)
Run 2: 11,810
Run 3: 11,760
Run 4: 11,790
Median: 11,790 ← report this
Taking the median of three real runs filters out one-off hiccups from background tasks or thermal spikes.
5. Record the conditions
A score without context is useless. Always note:
- GPU model and driver version
- Resolution and any quality settings
- Core/memory clock (stock or overclocked)
- Peak temperature and GPU utilization during the run
How to read your Volume Shader BM score
The score is a composite reflecting throughput across the workload. To interpret it:
- Compare like with like. A score is meaningful only relative to another score run under the same resolution and settings. Your 4K result is not comparable to someone's 1080p result.
- Check GPU utilization. If utilization sat below ~95% during the run, something else limited the card (CPU, power, or a software cap), and the score understates the GPU's potential.
- Watch the temperature trend. If your third run scored lower than your second, the card is likely thermal-throttling as it heats up — a sign your cooling is the bottleneck, not the silicon.
- Look at frame-time consistency, not just the total. Two cards can post similar scores while one is smooth and the other stutters. Consistency under load is part of "fast."
Using the benchmark to tune your system
Volume Shader BM is a perfect tuning tool because it is so repeatable:
| Change you made | What a higher score means |
|---|---|
| Raised core clock (overclock) | The overclock is stable and paying off |
| Lowered voltage (undervolt) | You kept performance while running cooler |
| Updated driver | The new driver genuinely improved throughput |
| Improved cooling | Less throttling = sustained higher clocks |
| Score dropped | Your change hurt performance — revert it |
Because the workload never changes, any score movement maps directly to a real performance change in your system. That makes it far more honest than a game benchmark, where patch updates and scene variation muddy the results.
Comparing two GPUs
If you are deciding between cards, run Volume Shader BM on both under identical settings and note the percent difference:
Card A: 11,790
Card B: 14,250
Card B is ~21% faster in this workload.
Remember that shader throughput is one dimension. Pair it with a VRAM bandwidth test and a broader GPU stress test to get the full picture — a card that wins on shaders can still lose on memory-bound workloads.
Common mistakes
- Trusting the first (warm-up) run. Always discard it.
- Comparing across resolutions and reading the gap as a card difference.
- Ignoring utilization. A sub-90% score says more about your system than your GPU.
- Running once. Variance is real; median of three.
- Forgetting to log conditions, making later comparisons impossible.
Conclusion
The Volume Shader BM benchmark is a powerful, deterministic way to measure the part of GPU performance that matters most for heavy rendering: shader and compute throughput. Run a warm-up, take the median of three passes under identical settings, record the conditions, and always check GPU utilization before trusting the number. Used this way, it becomes both a reliable comparison tool and the single best way to prove that your overclocks, undervolts, and driver updates are actually doing something.