Quick wins for a faster PC:
Clear out junk files and repair common Windows errorsFree Scan →Scan for outdated or missing drivers - takes under a minuteDriver Scan →Repair Windows errors before they cause bigger problemsFix Now →To measure an SSD’s sustained write speed after its fast write region fills, run a long, controlled sequential write and record throughput throughout the run. Report the initial burst separately from a stable post-drop interval. A short benchmark score cannot establish post-cache speed.
What this benchmark measures
A long sequential-write trace answers a specific question: how quickly the drive writes a sustained stream of data after its initial fast region. It does not measure random-write IOPS, and it should not be confused with a formal steady-state random-write test. Those workloads answer different questions. fio, for example, documents SPRandom as a preconditioning method for steady-state random-write workloads; it is not a substitute for this sequential test. See the fio documentation.
As an Amazon Associate I earn from qualifying purchases.
SSD performance depends on the drive’s state, workload and test environment. SNIA notes that fresh-out-of-box peak behavior differs from steady-state behavior and that preconditioning matters for formal measurement. Its Solid State Storage guidance also cautions: “SSDs behave very differently than HDDs, and standard HDD benchmarks will not provide a true picture of SSD performance.” See SNIA’s Solid State Storage resource.
Prepare the drive and record its state
Back up important data and confirm the target before starting. A raw-device write test can overwrite the selected device. A file-based test avoids targeting a raw block device, but includes filesystem and free-space effects; record which approach you use. Monitor temperature during the run rather than leaving it unattended.
#1 Best Overall
- MEET THE NEXT GEN: Consider this a cheat code; Our Samsung 990 PRO Gen4 SSD helps you reach near max performance with lightning-fast speeds; Whether you’re a hardcore gamer or a tech guru, you’ll get power efficiency built for the final boss
- REACH THE NEXT LEVEL: Gen4 steps up with faster transfer speeds and high-performance bandwidth; With a more than 55% improvement in random performance compared to 980 PRO, it’s here for heavy computing and faster loading
- THE FASTEST SSD FROM THE WORLD'S FLASH MEMORY BRAND: The speed you need for any occasion; With read and write speeds up to 7450/6900 MB/s you’ll reach near max performance of PCIe 4.0 powering through for any use
- PLAY WITHOUT LIMITS: Give yourself some space with storage capacities from 1TB to 4TB; Sync all your saves and reign supreme in gaming, video editing, data analysis and more
- IT’S A POWER MOVE: Save the power for your performance; Get power efficiency all while experiencing up to 50% improved performance per watt over the 980 PRO; It makes every move more effective with less consumption
Record enough detail for another person to understand the result and reproduce the conditions:
- Drive model, capacity and firmware
- Interface and negotiated link, plus the host and operating system
- Test program and version
- Cooling and drive temperature
- Whether the drive is fresh, partly filled or previously written
- For a file test, the filesystem and available free space; for a raw test, the target device
For comparisons, keep the host path, drive fill, temperature, workload settings and measurement window as similar as practicable. SNIA’s performance work treats test hardware, software, settings, methodology and procedure as factors in repeatable SSD comparisons. Its Performance Test Specifications are designed for standardized client and enterprise SSD comparison and recommend a Reference Test Platform.
Rank #2
- Ideal for high speed, low power storage
- Gen 4x4 NVMe PCle performance
- Up to 6,000MB/s read, 4,000MB/s write
- Includes Acronis cloning software
- 5-year limited warranty
Choose settings for a sequential-write question
Use a consistent sequential write pattern and a block size that reflects the large-copy workload you want to represent. Record the block size, queue depth, job count, direct-I/O or buffered-I/O setting, and whether writes are flushed or synchronized. These choices affect what the result represents; do not present a random-write IOPS score as sequential throughput.
The Tool Desk
Outbyte Driver Updater FREEFix the driver behind crashes, sound loss and screen glitchesFind Drivers →Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →fio is a flexible I/O generator, not a guarantee of a particular result. Its documentation defines bs as the I/O unit size. Disclose the actual settings you use rather than describing a run only as “fio tested.”
Rank #3
- SPEED UP PROJECTS. Launch creator applications fast with uncompromising PCIe 4.0 read speeds up to 7,100MB/s,[2] (1TB and 2TB[1] models) and write speeds up to 6,700MB/s[2] (1TB[1]-4TB[1] models).
- CREATE AND STORE MORE. Make more room for your 4K videos and high-resolution images with capacities from 500GB[1] up to 4TB[1] on M.2 2280 built with our trusted 8th generation SANDISK BiCS QLC 3D CBA NAND.
- IT GOES WHERE YOU GO. With an all-new power efficient design, your drive delivers high performance with low power, giving you more time to be productive while on the go.
- UNCOMPROMISED RELIABILITY. With up to 1,200 TBW[3] (4TB[1] model) endurance rating, your drive is designed for creators.
- KEEP YOUR DRIVE UPDATED. Monitor your SSD’s performance and check for updates with the downloadable SANDISK Dashboard application.[5]
Run long enough to capture the change
Write enough data to get beyond the drive’s current fast write region, then continue long enough to see whether throughput settles, oscillates or recovers. There is no universal time or number of gigabytes that guarantees the cache has filled. Behavior can vary with model, capacity, free space, previous writes, temperature and background cleanup. Do not assume the cache is exhausted just because a guessed cache-size figure has been reached.
Save a throughput trace against elapsed time or cumulative bytes written. Also retain temperature, pauses and the workload settings. Short, fixed measurement intervals make it easier to see the burst-to-sustained transition and any later dips.
Rank #4
- HUGE SPEED BOOST: Get random read/write speeds that are 40%/55% faster than 980 PRO; Experience up to 1400K/1550K IOPS, while sequential read/write speeds up to 7,450/6,900 MB/s reach near the max performance of PCIe 4.0*
- BREAKTHROUGH POWER EFFICIENCY: Use less power and get more performance; Enjoy up to 50% improved performance per watt over 980 PRO, plus optimal power efficiency with max PCIe 4.0 performance**
- SMART THERMAL CONTROL: Samsung's own nickel-coated controller delivers effective thermal control; With its slim size, 990 PRO is a perfect fit for desktops and laptops that meet the PCI-SIG D8 standard***
- THE CHAMPION MAKER: Up to 65% improvement in random performance enables faster loads for an ultimate gaming experience on PS5 and DirectStorage PC games****
- SAMSUNG MAGICIAN SOFTWARE: Get the most out of your SSD with Samsung Magician's advanced yet intuitive optimization tools; Monitor drive health, protect valuable data, and receive important updates for your 990 PRO
Report the initial burst separately, identify the point or range where throughput fell, and calculate an average or median for a clearly identified stable post-transition window. If the trace has no distinct drop or stable interval, say so and present the trace rather than claiming a post-cache figure.
Do these 3 things before closing this tab:
1Scan for outdated or missing drivers - takes under a minute2Clear out junk files and repair common Windows errors3Fix the driver behind crashes, sound loss and screen glitchesRepeat runs and compare drives fairly
Repeat the test from a documented drive state. If you want to compare cooled drives, use a consistent idle or cooling period; if you want to model uninterrupted real-world writes, do not add an idle period that the workload would not have. Keep drive fullness consistent and state it, since a nearly empty drive and a heavily occupied drive may not behave alike.
Best Value
- This product has been replaced by our latest generation. Please search for the SANDISK Optimus GX 7100 NVMe SSD
- HIGH-OCTANE GAMING. Experience speeds up to 7,250MB/s read and 6,900MB/s write (1-2TB models), with up to 35% faster performance than previous generation.
- PURPOSE-BUILT. Designed for serious on-the-go gamers, with a PCIe Gen4 interface and SANDISK’s next generation TLC 3D NAND.
- MORE TIME TO CLEAR THAT CHECKPOINT. Built with laptops and handheld gaming devices in mind, with up to 100% more power efficiency over the previous generation.
- DO MORE WITH DASHBOARD. Ensure your drive is optimized for prime performance with the downloadable WD_BLACK Dashboard (Windows only).
For each drive, compare the same parts of the trace and disclose:
- Where the burst-to-sustained transition occurs
- Sustained sequential MB/s or GB/s over the same measurement window
- Variation, periodic dips or recovery
- Temperature and possible thermal throttling
- Drive fill state and whether the run was file-based or raw-device
Sequential throughput is only one dimension of storage performance. If the intended workload involves random access or write endurance, assess those separately. SNIA notes that workload content and intensity affect observed bandwidth and response time.
Interpret a slowdown without overclaiming
A sharp or gradual drop after fast writes is consistent with moving beyond a limited high-speed write region, but this trace alone does not reveal the controller’s internal cache policy. Other factors can also shape the result:
Free tools Windows power users keep installed
One-click scans. No signup required.
- Thermal throttling
- Host or interface limits
- Filesystem behavior in a file-based run
- Background garbage collection or cleanup
- Drive fullness
- Write durability settings
Check temperature and host-link limits, then repeat under controlled conditions before attributing a drop to a particular cause. The result of a practical desktop fio run can answer an individual workload question, but it is not a SNIA-compliant result unless the applicable specification and setup were followed. SNIA’s Performance Test Specifications define a standardized comparative approach; a single consumer test should not be labeled as such.
What to include when publishing a result
A useful report lets readers see both the conditions and the evidence behind the number. Include the drive state, test path and workload settings alongside the trace, and label the interval used for any sustained-speed statistic. Do not turn one drive’s observed result into a model-independent cache size or post-cache speed: neither is universal.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
