Are Dramless SSDs really that bad (stutter?)

[AmyTheBun]

I keep hearing everywhere that DRAM-less SSDs all stutter if used as the main drive(games, steam, and windows itself)

 

should one buy a smaller dram having ssd for windows and only reserve dramless ones for bulk storage? there's like a 40$ difference between the sn550 and sn750 at 1tb on amazon!

 

Is this just a myth? anyone had real life experiences having used both of those ssds on a system as the boot drive?

[NewMaxx]

SATA ones are definitely inferior. NVMe is a different story, the SN550 is actually a very good drive. And yes I own the SN550, two SN750s, and several DRAM-less SATA drives.

[AmyTheBun]

4 minutes ago, NewMaxx said:

SATA ones are definitely inferior. NVMe is a different story, the SN550 is actually a very good drive. And yes I own the SN550, two SN750s, and several DRAM-less SATA drives.

Oh so that quote is from the sata days of ssds? makes sense thanks

 

[NewMaxx]

Yes. It's not just about DRAM, the AHCI protocol (which SATA SSDs use) is inferior for solid state which is why NVMe was introduced. Further, DRAM-less drives (and again, especially SATA) tend to be marketed towards a budget segment so may have weaker controllers and usually large SLC caching schemes which are less reliable especially when the drive is fuller (which is why AnandTech's review of the Mushkin Source states that you must consider/compare them as being less in capacity). DRAM-less NVMe drives get around the protocol limitations and also use host memory buffer (HMB) to use some system memory for mapping which helps alleviate that issue as well. NVMe controllers are more powerful, too. And some drives, like the SN550, have conservative SLC caches with solid native flash performance, which is why it performs so well in reviews and is incredibly consistent even when fuller.

 

I have tons of SSDs (just google my name) but I avoid using DRAM-less SATA for anything but storage wherever possible. I only have one old system where it's primary and I can immediately tell when I use it, but some people claim not to notice (although it's more of an issue when fuller). Keep in mind this is disregarding TLC vs. QLC - a QLC DRAM-less drive will be even worse, especially with SATA, like the SU630/SU635, and especially at lower capacities due to higher flash density (fewer dies). To learn more, again, google me, I also have a discord server, etc.

[Senzelian]

Very good explenation @NewMaxx

Edit: Joined your subreddit

 

@AmyTheBun What you should take away from this is, that HMB is a way of replacing DRAM, with simiar performance, but does only work with NVMe drives.

[NewMaxx]

HMB does require driver/OS support but any newer Windows 10 build will work with it fine. The SN550's predecessor, the SN500, actually did not use HMB but also didn't really need it; the WD drives have extra dedicated SRAM for mapping which is sufficient for consumer workloads/worksets. The SN550 I can confirm uses HMB (you can check and even adjust this) but it also does not need it thanks to efficient SRAM usage, although if it matters - it can use up to 64MB of system RAM for mapping. There are several tricks to getting around the mapping limitations but further, NVMe is fast and efficient enough with SLC that you are unlikely to jam the drive - again thanks to its powerful controller (scaled down from the SN750's) and static SLC design (it never needs to hit a folding state, but that requires a more technical explanation).