iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
For most everyday laptops and desktops, a good DRAMless NVMe SSD with Host Memory Buffer (HMB) is fast enough for booting, applications and game loading. Dedicated DRAM becomes more valuable when you need sustained writes, highly random or concurrent I/O, virtualization, database-like work or consistently low latency. DRAM stores an SSD’s flash-translation mapping in a fast local workspace. A DRAMless drive keeps more of that mapping in NAND and can cache selected metadata in the computer’s system memory through HMB. HMB narrows the gap, but it is not a full substitute for onboard DRAM in every workload.
What does DRAM do inside an SSD?
An SSD presents the operating system with logical block addresses, while its NAND flash stores data in physical pages and blocks. The controller maintains a flash-translation layer (FTL) that maps each logical address to the physical location holding the data. Samsung describes DRAM as a high-speed cache for this mapping table, allowing the controller to find and update NAND locations without repeatedly reading mapping metadata from flash.
Dedicated DRAM gives the controller a fast local workspace for frequently used FTL information. Firmware may also use that memory for temporary read or write data, although the exact policy differs by controller and model. Because DRAM is much faster than NAND for small random accesses, it can reduce lookup latency and help a drive maintain steadier behavior when many requests arrive at once.
- Mapping lookups: Frequently accessed address translations can remain in fast memory.
- Random I/O: The controller spends less time fetching metadata before servicing small reads and writes.
- Concurrency: A larger local workspace helps when several applications or virtual machines issue requests simultaneously.
- Consistency: Under demanding workloads, onboard DRAM can reduce long-delay (“tail latency”) events, though NAND, firmware and cooling still matter.
DRAM is not the NAND itself and does not increase the number of writes the flash cells can survive. It is a performance resource used by the controller.
#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
What does “DRAMless” mean on an NVMe SSD?
A DRAMless SSD omits a dedicated DRAM package on the drive’s circuit board. Its FTL metadata is kept partly in NAND, where access is slower, and the controller may use its own SRAM plus HMB to keep selected information closer at hand. “DRAMless” therefore describes the drive’s architecture, not a promise that it has no memory at all.
NVMe Host Memory Buffer (HMB) allows a compatible SSD controller to reserve a small region of the host computer’s system DRAM. Western Digital introduced HMB as a way to reduce the need for onboard DRAM. The operating system and driver determine whether HMB is available and how it is allocated; support and behavior can vary by platform.
In the peer-reviewed PLOS ONE experiments by Kim and Kim (2020), commercial DRAMless products had clearly worse I/O performance than comparable drives with controller DRAM. Enabling HMB improved the DRAMless results, but the tested drives mainly used HMB as an address-mapping-table cache rather than as a large general-purpose read cache or write buffer. HMB narrows the difference; it does not make every DRAMless SSD equivalent to a DRAM-equipped model.
Is HMB the same thing as an SLC cache?
No. HMB uses host system DRAM for controller metadata, chiefly address-mapping information in the cited tests. A pseudo-SLC cache uses a portion of the SSD’s NAND in a faster operating mode to absorb burst writes before data is folded into its normal flash format.
| Resource | Where it resides | Main purpose | What it does not guarantee |
|---|---|---|---|
| Dedicated DRAM | On the SSD | Fast FTL workspace; firmware may also use it for temporary data | It does not prevent all post-cache write slowdowns or extend NAND endurance by itself |
| HMB | Reserved host system DRAM | Selected controller metadata, especially mapping-table entries | It is not an SLC cache and is not a full replacement for onboard DRAM |
| Pseudo-SLC cache | NAND on the SSD | Absorbs burst writes in a faster NAND mode | Its capacity and post-cache speed vary with free space, firmware and workload |
A drive can use dedicated DRAM, HMB, pseudo-SLC, more than one of these, or none of them. Check the controller and manufacturer documentation instead of inferring one feature from another.
Rank #2
- THE SSD ALL-STAR: The latest 870 EVO has indisputable performance, reliability and compatibility built upon Samsung's pioneering technology.Computer Platform:PC.Encryption : Class 0 (AES 256) TCG/Opal v2.0, MS eDrive (IEEE1667), Environmental Specs - Shock : 1,500 G & 0.5 ms (Half sine).
- EXCELLENCE IN PERFORMANCE: Enjoy professional level SSD performance with 870 EVO, which maximizes the SATA interface limit to 560/530 MB/s sequential speeds, Accelerates write speeds and maintains long term high performance with a larger variable buffer
- INDUSTRY DEFINING RELIABILITY: Meet the demands of every task from everyday computing to 8K video processing, with up to 2,400 TBW
- MORE COMPATIBLE THAN EVER: 870 EVO has been compatibility tested for major host systems and applications, including chipsets, motherboards, NAS, and video recording devices. Interface- SATA 6GB/s, compatible with SATA 3GB/s and SATA 1.5GB/s interfaces
How much slower is a DRAMless SSD?
There is no single percentage that applies to every model. The gap depends on request size, queue depth, read/write mix, whether the workload is sustained, the NAND type, controller firmware, capacity and temperature. Objective Analysis analyst Jim Handy wrote on 19 August 2025 that light-I/O applications perform similarly on both designs, with the DRAMless drive typically slightly slower, and that the difference is seldom noticed in office applications.
| Workload | Likely outcome | Why the difference appears |
|---|---|---|
| Booting and launching applications | Often close between a well-designed HMB drive and a DRAM model | Requests are relatively bursty, and idle time lets the controller complete metadata work |
| Web browsing and office documents | Usually little noticeable difference | I/O activity is light and intermittent; the drive is rarely saturated |
| Game loading | Often similar in practical use | Loads are generally read-heavy bursts rather than hours of continuous writes |
| Highly random, concurrent I/O | Dedicated DRAM is usually preferable | Many simultaneous lookups increase metadata traffic and expose latency spikes |
| Long sequential or mixed writes | Differences can become substantial after temporary write cache fills | NAND speed, cache policy, controller thermals and free capacity dominate sustained behavior |
| Virtual machines and database-like work | DRAM models are the safer choice for consistency | Small random requests and concurrency keep the FTL busy continuously |
Sequential headline numbers are therefore an incomplete buying signal. A drive advertised at a high peak speed can still slow sharply during a long transfer, and onboard DRAM does not eliminate that behavior. Look for post-cache write results, random-I/O latency and thermal data for the exact capacity.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
Does DRAM make an SSD last longer?
Not automatically. NAND flash has finite write endurance. Kingston explains that wear levelling spreads writes across cells so that a small group is not exhausted early, while over-provisioning reserves capacity for replacement blocks and background operations. Those mechanisms, along with NAND type, firmware, workload and cooling, influence service life.
Use the manufacturer’s endurance rating for the exact capacity, expressed as total bytes written (TBW) or drive writes per day (DWPD), rather than treating DRAM as a longevity rating. Also check the warranty period and whether the rating applies to a particular workload or product family.
Samsung’s official 980 information illustrates why capacity matters: its family is rated for up to 600 TBW and a five-year limited warranty, while the 2022 datasheet lists 150 TBW for 250GB, 300 TBW for 500GB and 600 TBW for 1TB. These are Samsung manufacturer figures, not independent test results. A larger model may have a higher TBW rating because it contains more NAND, even when the architecture is otherwise similar.
Rank #3
- 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
What is the difference between the Samsung 980 and 980 PRO architectures?
These models provide a clear example of the architecture distinction, not a rule that every drive from a manufacturer behaves the same way. The Samsung 980 datasheet lists no dedicated DRAM cache and the product page identifies HMB. The 980 PRO datasheet lists dedicated LPDDR4 DRAM whose amount varies by capacity.
| Model example | Controller-memory design | Interface and published figures | Capacity details |
|---|---|---|---|
| Samsung 980 | DRAM cache memory listed as “-”; uses HMB | PCIe 3.0 x4, NVMe 1.4; up to 3,500 MB/s sequential read and 3,000 MB/s sequential write | 250GB, 500GB and 1TB; family up to 600 TBW and five-year limited warranty |
| Samsung 980 PRO | Dedicated LPDDR4 DRAM | Amount depends on capacity; consult the model’s datasheet | 512MB, 1GB or 2GB LPDDR4 DRAM depending on capacity |
Firmware revisions, NAND changes, capacity and cooling can alter real results, so use these as documented architecture examples rather than assuming all 980 or 980 PRO units perform identically.
Should I buy a DRAMless SSD for gaming or a normal desktop?
Choose a reputable HMB-based DRAMless model when the system mainly boots, launches applications, browses, handles documents or loads games, and a lower price, lower power draw or smaller board footprint matters. These workloads usually do not keep the FTL under constant random-I/O pressure.
Dedicated DRAM is worth prioritizing when the SSD will sustain heavy writes, serve several virtual machines, run database-like random workloads, handle large working sets or support an application with strict latency consistency. It is also the less uncertain choice if the price difference is small and you expect the workload to grow.
- Everyday laptop or family desktop: HMB DRAMless is generally an appropriate value choice.
- Gaming library drive: HMB can be adequate; prioritize capacity, thermals and sustained behavior over a DRAM label alone.
- Content creation scratch or ingest drive: Compare post-cache write speed and endurance; choose dedicated DRAM when writes are frequent and concurrent.
- Virtualization, databases or professional storage: Favor dedicated DRAM and examine random-I/O latency, firmware support and warranty terms.
- Thin laptop with strict power limits: The lower board area and power demand of a DRAMless design can be useful, provided the platform supports HMB.
What should I check before buying either type?
Use this checklist for the exact model and capacity. A DRAM label is only one item in a broader storage decision.
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsRank #4
- Upgrade your laptop or desktop computer and feel the difference with super-fast OS boot times and application loads
- Exceptional performance offering up to 535MB/s seq. Read and 500MB/s seq. Write speeds
- Superior performance as compared to traditional hard drives (HDD)
- Ultra-low power consumption
- Backwards compatible with SATA II 3GB/sec
- Confirm the form factor and key: Verify that the M.2 length and connector key fit the motherboard or laptop slot.
- Check the PCIe generation: Match the drive’s interface to the system. A faster-generation SSD in a slower slot will operate at the slot’s limits.
- Verify operating-system HMB support: A DRAMless drive depends on platform and driver support for its host-memory feature.
- Identify the NAND type and controller: Firmware and flash selection affect sustained speed, latency and endurance.
- Find post-cache write behavior: Look for measurements after the temporary write cache is exhausted, not only peak sequential figures.
- Review random-I/O latency: Queue depth and mixed-read/write results are more informative for multitasking than a single sequential number.
- Plan thermal clearance: Check whether the slot has a heatsink or adequate airflow; throttling can erase the advantage of either architecture.
- Compare capacity-specific TBW or DWPD: Do not apply a 1TB rating to a 500GB model.
- Read the warranty terms: Confirm duration, endurance limits and any workload conditions.
- Compare current price: A modest premium for dedicated DRAM may be sensible for a heavy workload, while an inexpensive HMB drive can deliver the same everyday feel.
What are the common mistakes when comparing DRAM and DRAMless SSDs?
Assuming DRAM automatically means faster in every task
Light desktop I/O can feel nearly identical because neither drive is saturated. DRAM’s advantage is most visible in metadata-heavy, random or sustained workloads.
Treating HMB as a large extension of onboard memory
HMB is a selected host-memory region, and the cited PLOS ONE tests found it used mainly for mapping-table caching. It cannot be assumed to provide the same general-purpose workspace as a dedicated DRAM package.
Using sequential peak speed as the whole verdict
Peak figures describe short, favorable conditions. Long transfers, a full pseudo-SLC cache, high temperature and low free space can produce a very different result.
Judging endurance from the presence of DRAM
TBW or DWPD, NAND, wear levelling, over-provisioning, firmware and cooling determine the endurance picture. DRAM alone is not a lifespan guarantee.
Free tools Windows power users keep installed
One-click scans. No signup required.
Comparing different capacities as if they were identical
Capacity can change NAND channel parallelism, cache size, TBW and DRAM amount. Compare like-for-like capacities and read the exact datasheet.
Best Value
- THE SSD ALL-STAR: The latest 870 EVO has indisputable performance, reliability and compatibility built upon Samsung's pioneering technology. S.M.A.R.T. Support: Yes
- EXCELLENCE IN PERFORMANCE: Enjoy professional level SSD performance which maximizes the SATA interface limit to 560 530 MB/s sequential speeds,* accelerates write speeds and maintains long term high performance with a larger variable buffer, Designed for gamers and professionals to handle heavy workloads of high-end PCs, workstations and NAS
- INDUSTRY-DEFINING RELIABILITY: Meet the demands of every task — from everyday computing to 8K video processing, with up to 600 TBW** under a 5-year limited warranty***
- MORE COMPATIBLE THAN EVER: The 870 EVO has been compatibility tested**** for major host systems and applications, including chipsets, motherboards, NAS, and video recording devices
- UPGRADE WITH EASE: Using the 870 EVO SSD is as simple as plugging it into the standard 2.5 inch SATA form factor on your desktop PC or laptop; The renewed migration software takes care of the rest
How can I make the choice quickly?
Start with the workload, then use the architecture as a tie-breaker.
- If your use is mostly booting, office work, browsing and gaming, select a reputable HMB model with the required capacity, warranty and thermal fit.
- If you write large amounts continuously or run many random requests at once, select dedicated DRAM and verify post-cache results.
- If the two candidates cost nearly the same, dedicated DRAM buys more headroom for future heavier workloads.
- If the DRAMless model is substantially cheaper or more power-efficient and your workload is light, the practical difference may be too small to justify the premium.
The right upgrade is the one whose interface, thermals, endurance and sustained behavior fit your system. DRAM is an important indicator of controller design, but it is not a substitute for evaluating the complete drive.
Frequently Asked Questions
Can a DRAMless SSD work in an older computer?
Compatibility depends on the slot, PCIe generation, M.2 key and the operating system’s NVMe and HMB support. The drive may still function in a compatible slot at a lower link speed, but HMB behavior can differ by platform, so check the computer and SSD documentation before buying.
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 →Will adding more system RAM make a DRAMless SSD faster?
HMB reserves only a controller-selected region of host memory; installing extra RAM does not automatically enlarge that region or turn the drive into a DRAM model. It can help overall system multitasking, but SSD behavior remains controlled by the drive’s firmware and driver.
Does a DRAMless SSD lose data if the computer loses power?
The DRAMless label alone does not determine power-loss protection. Consumer drives generally rely on firmware and NAND management rather than enterprise-grade capacitors, so evaluate the specific model’s power-loss specifications and keep current backups.
Is a DRAMless SSD a good secondary game drive?
Usually, yes, when the drive has adequate capacity, cooling and a suitable warranty. Game loading is commonly bursty and read-heavy, but large installations, updates and simultaneous downloads can expose post-cache write limits.
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.
