I’ve heard that dramless SATA ssds are pretty bad compared to those with DRAM, but what about m.2 ssds? Do they have the same issues?
It works similarly. Some NVME SSDs use something called Host Memory Buffer (HMB) to borrow some of your system RAM as cache, but that’s not as good as having dedicated DRAM. Keep in mind, not all SSDs support HMB.
Also, M.2 SSDs can be either NVME (PCIe) or SATA. Just saying ‘M.2’ doesn’t tell you which one you’re dealing with.
@Tom
I would never buy M.2 SATA, and I doubt anyone would. I’m asking about the difference in performance between DRAM and DRAMless versions of both SATA and NVME. I’ve heard the SSD I’m interested in (Patriot P300) supports HMB, how can I check for sure?
There’s a lot of confusion about DRAM on SSDs and what it actually does. DRAM is not a cache for read/write operations. It’s used to store the data map, which tells the SSD where to read from and write to. DRAM is much faster than NAND flash, so it makes the process faster.
If the SSD doesn’t have DRAM or HMB, that map will be stored in the NAND, which slows everything down.
Some people think DRAM is for faster read/write speeds, but that’s not the case. DRAM’s job is to make the SSD faster by storing the data map. When the SSD is DRAMless, that map is written to the NAND, which slows it down.
HMB is like a workaround. It uses your system RAM, which is faster than NAND but slower than DRAM. Some newer drives use HMB so well that their performance is really close to DRAM-based drives.
You don’t need to rule out drives just because they don’t have DRAM unless you’re looking for top-end performance.
Check out reviews from places like Techpowerup or Tom’s Hardware to get a feel for how good a drive is, DRAM or not.
Here are a few drives that don’t have DRAM but perform well with HMB:
https://www.techpowerup.com/review/lexar-nm790-2-tb/
https://www.techpowerup.com/review/wd-blue-sn580-1-tb/19.html
https://www.techpowerup.com/review/team-group-a440-lite-2-tb/
@Ciel
Just adding to this: When writing to the drive, SSDs use SLC (Single-Level Cell) cache to boost write speeds. If the drive has a small cache, it can fill up quickly and slow down. Some cheaper drives with QLC (Quad-Level Cell) NAND may have small caches, which leads to slower speeds under sustained writes.
Having DRAM doesn’t help much if the drive uses slow NAND or doesn’t have a large cache. Some DRAMless drives, though, still perform well with fast NAND and a bigger cache, like the Team Group A440 Lite.
In most cases, I wouldn’t bother with DRAMless SSDs. They often perform as poorly as hard drives, especially if they’re cheap, because they likely don’t use fast memory chips.
That DRAM is important for real-world performance since it caches data for faster access. Drives without it can be a lot slower. LTT did a video about this. There are some cases where DRAM isn’t needed, but for most people, that’s not the case.
TLDR: If an SSD doesn’t have DRAM, it’s probably too cheap to offer much speed over hard drives, so it’s not really an upgrade.
@Campbell
Are you sure about that? I’ve heard HMB can make DRAMless SSDs almost as fast as those with DRAM. I’ve also noticed my SATA SSDs are a lot faster than my friend’s HDD (like 5x faster to extract a game, for example).
@LIZAH
Maybe not 99%, but an SSD and motherboard need to be compatible with HMB, and it has to be set up right. I personally don’t bother because I think of storage as something I’ll use for external drives when I upgrade.
@Campbell
How can I check if mine will work? I’ve got an MSI B550A Pro, and I’m planning on buying the Patriot P300 512GB.
LIZAH said:
@Campbell
How can I check if mine will work? I’ve got an MSI B550A Pro, and I’m planning on buying the Patriot P300 512GB.
Patriot P300 512GB
Your motherboard has two M.2 PCIe ports. The top one connects to the CPU and will be faster. The second one is limited to PCIe 3.0, but the P300 will work in either slot.
In terms of speed:
A SATA SSD is about 100x faster than a hard drive, and an M.2 PCIe SSD is around 1000x faster. That said, M.2 drives without DRAM are about half the speed of those with DRAM. But even DRAMless M.2 drives are way faster than SATA SSDs.
If you get one with DRAM, it will be quicker, but in everyday use, you probably won’t notice. I went from a WD Blue M.2 without DRAM to a WD Black with DRAM, and it only feels like it loads faster.
@Thunderfall
Thanks for the info, that clears things up!
LIZAH said:
@Campbell
How can I check if mine will work? I’ve got an MSI B550A Pro, and I’m planning on buying the Patriot P300 512GB.
Just chiming in, I went with the 980 Pro 2TB. I didn’t pay much attention to DRAM, just went with anything labeled ‘NVMe’.
@Brads
Yeah, I trust it less these days since it makes a lot of mistakes, but thanks anyway!