User Experiences with CrystalDiskMark

“I installed a PCIe 4.0 NVMe drive and wanted to confirm it wasn’t limited by the slot or drivers. I ran CrystalDiskMark with the default 1 GiB test a few times. Sequential read was around 7,000 MB/s and write around 5,000 MB/s, which matched the specs. I also ran the Real World profile to see more realistic numbers. CrystalDiskMark made it easy to see that the drive was performing as expected.”

Takeaway: Use both default (Peak) and Real World tests to get a full picture of your drive’s performance.

“I needed to benchmark a NAS volume mapped as Z:\. CrystalDiskMark only showed C: and D:\. I found that when you run as Administrator (UAC Yes), network drives are hidden. I closed the app, started it again, and when the UAC dialog appeared I clicked No. After that, Z: appeared in the drive list and I could run the benchmark. Throughput was lower than local SSDs, as expected, but the test completed without errors.”

Takeaway: For network drives, run CrystalDiskMark without Administrator rights. See FAQ – Network drive.

“On my work PC, CrystalDiskMark kept failing when I clicked All. The error suggested it couldn’t create the test file. I right‑clicked the CrystalDiskMark shortcut, chose ‘Run as administrator’, clicked Yes at UAC, and ran the test again. It completed successfully. So for local drives, if the benchmark fails, try running as Administrator.”

Takeaway: Local drive benchmark failing often means insufficient rights; run as Admin. See FAQ – Benchmark failed.

“I had an old SATA SSD and was considering an NVMe upgrade. I benchmarked both with CrystalDiskMark using the same settings (1 GiB, 5 runs). The SATA SSD did about 550 MB/s sequential read and 520 MB/s write. The new NVMe did about 3,400 MB/s read and 2,800 MB/s write. The random 4K results also showed a big difference. That gave me clear numbers to justify the upgrade for video editing.”

Takeaway: Use the same test size and run count when comparing two drives.

“I ran CrystalDiskMark and another popular benchmark on the same SSD and got different MB/s values. I learned that tools use different test data (e.g. random vs 0fill), block sizes, and queue depths, so numbers don’t have to match. What matters is comparing the same drive with the same tool before and after a change, or comparing two drives with the same tool and settings. CrystalDiskMark’s results are consistent when you keep settings the same.”

Takeaway: Don’t expect identical numbers across different software; see FAQ – Results differ.

“I was testing a USB 3.0 flash drive. With the default 1 GiB test it took a very long time. I changed the test size to 64 MiB or 128 MiB in CrystalDiskMark, and the benchmark finished in a reasonable time. The results (around 80 MB/s read, 20 MB/s write) helped me confirm the drive was working within typical USB 3.0 limits. For slow storage, use a smaller test size.”

Takeaway: For USB memory and other slow devices, choose a smaller test size (e.g. 64 MiB or 128 MiB) in the main window.

“I was confused because Peak showed 6,500 MB/s but Real World showed around 4,200 MB/s on my NVMe. I read that Peak uses settings that maximize throughput (e.g. deep queue), while Real World mimics more typical use. For sharing with friends or forums I still use Peak, but for my own decision (e.g. upgrading) I look at Real World. Both are valid—Peak for ‘best case,’ Real World for ‘everyday.’”

Takeaway: Use Peak for headline comparison and specs; use Real World for realistic expectations. See Guide – Test profiles.

“I cloned my Windows HDD to a new SATA SSD using cloning software. Before cloning, I ran CrystalDiskMark on the HDD: about 120 MB/s sequential read. After cloning and booting from the SSD, I ran the same test on the new drive: about 520 MB/s read. The PC felt much snappier; CrystalDiskMark gave me the numbers to confirm the upgrade was worth it.”

Takeaway: Benchmark before and after a clone or upgrade with the same settings to see the real-world improvement.

“My SSD was acting slow and I wanted to document it for a possible RMA. I ran CrystalDiskMark, then used the menu to save the result as an image and also copied the text to a file. I sent both to support. They acknowledged the numbers were below spec and processed the replacement. Having the screenshot and exact MB/s values helped a lot.”

Takeaway: Use Copy and Save as Image from the program menu to keep a record for support or warranty. See FAQ – Save results.

“My new PCIe 4.0 NVMe was only showing around 1,800 MB/s instead of 5,000+. I ran CrystalDiskMark a couple of times to confirm. Then I checked the motherboard manual: my second M.2 slot only runs at PCIe 3.0 x2. I moved the drive to the primary slot (PCIe 4.0 x4) and ran the benchmark again. Sequential read jumped to over 5,000 MB/s. CrystalDiskMark made it obvious something was limiting the drive; the manual and BIOS confirmed the cause.”

Takeaway: If NVMe results are far below spec, check which M.2 slot you use and whether it runs at full PCIe lanes and generation. See FAQ – Slow results.