DRAM vs DRAM-Less SSD: Gaming Speed and Endurance

What is a DRAM cache on an SSD?

An SSD stores data in NAND flash memory, but it also needs a map of where every piece of data lives. That map is called the flash translation layer. On a drive with a DRAM cache, that map is kept in a small amount of fast memory on the drive itself. This lets the drive find and update data quickly without waiting for the slower NAND. The DRAM cache acts as a high-speed scratchpad for the drive's controller.

A DRAM-less SSD has no dedicated memory on the drive. Instead, it borrows a small portion of the system's main memory to hold the map. This approach is called host memory buffer, or HMB. The drive uses the system's RAM through the PCIe connection, which is fast but shared with the rest of the system. When the system RAM is under heavy load, the HMB may not get enough bandwidth, which can slow down the drive.

The choice between DRAM and DRAM-less affects how the drive handles writes, especially when the write queue is deep. For a deeper look at SSD types, see SSD types explained.

How a DRAM cache affects game load times

For loading games and levels, the difference between a DRAM and a DRAM-less SSD is small. Both types of drive can read data quickly, and the map lookup is not the main bottleneck when reading large files. The speed of the NAND flash and the interface, such as PCIe 4.0 or PCIe 5.0, matter more for load times. A PCIe 4.0 vs PCIe 5.0 SSD comparison shows that the interface bandwidth has a bigger impact on sequential reads than the DRAM cache.

A DRAM cache becomes more important when the drive has to handle many small random reads and writes, like when the operating system is updating files or when a game saves progress. In those cases, the map lookup happens often, and having it in fast memory helps keep the drive responsive. For everyday gaming, the difference is rarely noticeable.

Sustained writes and drive endurance

When you install a large game or record gameplay, the SSD has to write a lot of data continuously. A DRAM cache helps the drive manage these writes by keeping the map updated in fast memory, which reduces the number of times the drive has to write to the NAND. This can help the drive maintain a more consistent write speed over long periods. Without a DRAM cache, the drive may need to flush the map to NAND more often, causing write speed dips.

A DRAM-less SSD relies on the host memory buffer, which is slower than a dedicated DRAM cache. During heavy sustained writes, the drive may have to pause and update the map in NAND more often, which can slow down the write process and cause extra wear on the NAND cells. Over time, this extra wear can reduce the drive's endurance. The endurance rating of a drive, often given in terabytes written (TBW), is a better indicator of how long it will last. Drives with a DRAM cache often have higher TBW ratings for the same NAND type.

For most gaming, the amount of sustained writing is modest. Installing a game writes a lot of data at once, but that is not a daily occurrence. Recording gameplay at high bitrates can also write continuously, but the total amount is still small compared to what a drive is designed to handle. If you plan to do heavy writes, such as video editing or frequent large file transfers, a DRAM cache drive is a better choice. See how much SSD storage is enough for gaming for capacity advice.

What to pick for your play

For a gaming PC, a DRAM cache is a nice feature but not a requirement. If you mainly install games and play them, a DRAM-less SSD will work fine. If you record gameplay, edit videos, or move large files often, a drive with a DRAM cache can help keep write speeds steady and reduce wear.

When you look at a prebuilt gaming PC's spec sheet, the storage section may not mention whether the SSD has a DRAM cache. You can check the drive model and look up its specifications. If the drive is DRAM-less, it may use HMB, which is common on modern NVMe drives. Many prebuilt systems use DRAM-less drives to keep costs down, but they still perform well for gaming.

The interface matters too. A PCIe 4.0 or PCIe 5.0 NVMe SSD will give you fast load times regardless of the DRAM cache. For most games, the difference between a DRAM and a DRAM-less drive is not noticeable. Focus on getting enough storage capacity for your game library, and consider a DRAM cache if you do heavy write work.

If you are choosing a new gaming PC, look at the storage options and see if the SSD has a DRAM cache. For a balance of speed and endurance, a drive with a DRAM cache is a good choice for a primary drive. For secondary game storage, a DRAM-less drive can save money without hurting performance. Check our best SSDs for gaming guide for recommendations.

What to pick for your play

Questions

Does a DRAM cache make games load faster?

Not by a noticeable amount. Load times depend more on the NAND speed and interface. A DRAM cache helps with random small writes and sustained writes, not with reading large game files.

Is a DRAM-less SSD bad for gaming?

No. For playing games, a DRAM-less SSD works well. It may slow down during heavy writes like installing a large game, but that is a temporary situation. For everyday gaming, you will not notice a difference.

How can I tell if an SSD has a DRAM cache?

Check the drive's specifications on the manufacturer's website. Look for terms like 'DRAM cache' or 'host memory buffer'. If the drive uses HMB, it is DRAM-less. Some retailers list this in the product details.

Does a DRAM cache affect SSD lifespan?

Indirectly. A DRAM cache reduces the number of writes to the NAND during heavy write tasks, which can reduce wear. But the endurance rating, given in terabytes written (TBW), is a better measure of lifespan. A DRAM-less drive with a high TBW rating can still last a long time.

Should I get a DRAM cache SSD for a gaming PC?

It depends on your use. If you do heavy writes like recording or editing, yes. If you only play games, a DRAM-less drive is fine. Either way, choose a reputable brand and check the TBW rating.

Can a DRAM-less SSD use HMB on any system?

HMB requires support from the operating system and the motherboard. Windows 10 and 11 support HMB. Most modern motherboards with NVMe slots also support it. If HMB is not available, the drive may fall back to slower performance.