How to Read AS SSD Benchmark Scores: Every Row Explained
An AS SSD Benchmark result window packs a lot into a small grid: four test rows, two columns of numbers, three scores at the bottom, and a strip of drive information at the top. Read in the right order, it tells you not just how fast a drive is, but where it is fast, where it is slow, and whether something in your system is holding it back. This guide walks through every element of the results screen, what it measures, and which direction is better. If you have not run the test yet, grab the tool from our download page first — it is portable, so there is nothing to install.
Start at the top: the drive information strip
Before looking at any speed numbers, read the lines above the grid. AS SSD shows the drive model, firmware version, controller or driver in use, the partition offset, and the total capacity. Two things here matter more than any score. First, the controller line tells you which storage driver the drive is running under — a legacy IDE-mode driver (often flagged as pciide) cannot use Native Command Queuing and will drag the random results down. Second, the alignment value should read OK. A misaligned partition shows as BAD and forces the drive to do extra work on almost every access. A low score with a BAD flag in this strip is a configuration problem, not a slow drive.
The Seq row: sequential speed
The first row, Seq, measures how fast the drive reads and writes one large 1 GB file in a single continuous stream. This is the number that resembles the headline speed on the box, and it is the best case a drive can achieve: no searching, no queue management, just sustained throughput. Sequential speed is what dominates when you copy a single large video file or install image. Higher is better, and the read and write columns often differ — many drives read considerably faster than they write. What the Seq row does not tell you is how the drive feels in everyday use, because an operating system rarely reads one file end to end. That is what the next two rows are for.
The 4K row: single-thread random speed
The 4K row measures reading and writing randomly scattered 4 KB blocks, one request at a time. The numbers look shockingly small next to the Seq row — tens of MB/s instead of hundreds or thousands — and that is normal. Random access to tiny blocks is the hardest work a drive does, and it is also the closest match to what Windows, applications and games actually request all day: small pieces of data from all over the drive. Of all the rows, this one tracks the subjective snappiness of a system most closely. A drive can post a huge Seq number and still feel ordinary if its 4K row is weak. We dig into that relationship in Sequential vs 4K scores.
The 4K-64Thrd row: random speed under load
4K-64Thrd repeats the 4K test but spreads the requests across 64 simultaneous threads. This exposes how well the drive and its controller handle a deep queue of commands — the scenario Native Command Queuing was built for, and the scenario where drives running in IDE mode fall behind, because IDE cannot queue commands this way. Server-style and multitasking workloads live here: many programs reading and writing at once. On a healthy modern drive this row is many times higher than the single-thread 4K row. If your 4K-64Thrd result is barely above your 4K result, suspect the driver mode shown in the top strip before you blame the drive.
The Acc.time row: access time
Acc.time is the only row where lower is better. It reports average access time in milliseconds, separately for read and write. The read figure is measured across the full capacity of the drive (a full-stroke measurement), while the write figure is measured with the 1 GB test file. Access time is latency: how long the drive takes to start delivering data, before throughput even enters the picture. Small differences here are a large part of why an SSD feels instant compared with a mechanical drive. We cover this row in depth in access time explained.
The scores at the bottom
Below the grid, AS SSD prints a read score, a write score and a bold total score. These are not extra measurements — they are a weighted summary of the rows above, calculated with a published simplified formula in which the sequential result counts for very little and the 4K results dominate. That weighting is deliberate: the score is designed to reflect responsiveness, not headline throughput. Two warnings belong with every total score. First, it is only meaningful against results produced by the same AS SSD version and the same test size, because both change the arithmetic. Second, a total on its own hides the shape of the result — always glance back at the rows to see why a drive scored what it scored. The full breakdown is in our guide to the AS SSD score formula.
The Copy-Benchmark: a separate, practical test
Under the Tools menu, the Copy-Benchmark runs three copy scenarios using the operating system’s own cached copy functions: ISO (two large files), Program (a folder of many small files) and Game (a mixture of large and small files). Each reports a speed in MB/s and a duration in seconds. Because it uses the OS cache rather than bypassing it, the Copy test behaves more like a real file copy than the synthetic rows do — and the Program scenario, with its swarm of small files, is usually the slowest of the three, for the same 4K reasons as above. Our dedicated walkthrough is the Copy-Benchmark explained guide.
A 60-second reading routine
When a fresh result appears, read it in this order: (1) top strip — driver mode and alignment both OK? (2) Acc.time — fractions of a millisecond, with no wild read/write gap? (3) 4K row — does it look proportionate to drives of the same class you have seen reviewed? (4) 4K-64Thrd — a healthy multiple of the 4K row? (5) Seq — in line with the interface the drive is connected through? (6) total score — compared only against same-version, same-test-size results for the same or similar drives. That routine catches almost every misleading result before it sends you shopping for a drive you do not need. To see how your numbers stack up, compare them with the verified review results collected in AS SSD scores compared, and if you are viewing results in IOPS instead of MB/s, switch back with the View menu — the two displays are explained in MB/s vs IOPS explained.