Question  Samsung 970 Evo Plus vs. Seagate FireCuda 520 but both in Intel PCIe 3.0 slot?

[4EvrYng]

I am trying to decide between Samsung 970 Evo Plus vs. Seagate FireCuda 520 for my new build. Build uses Intel X299 motherboard so “winner” will run in PCIe 3.0 slot, advantages of 4.0’s higher bandwidth for sequential throughput will not be a deciding factor.

What matters to me is how they would stack up in such layout in random access, especially at lower queue depth and thread count. Does anybody have such benchmark info, please?

 

[NewMaxx]

970 EVO Plus is the better drive regardless, in my opinion. I know some people love their 4.0 drives but they're nuts. Full-drive SLC caching has so many drawbacks if you're doing anything serious with the drive. Again, I suspect I'll ruffle some feathers saying that, but it's true. Yes, it's really nice for bursty sequentials which is what 4.0 is all about. And future drives will have full-drive SLC too in many cases (upcoming E18 drives). But the E16 is just a retrofitted E12 and was never meant for this, in my opinion it is a stopgap AMD poured money into to have a selling point only.

Depends on what you're doing, though. On 3.0 it doesn't matter as much, in the short-term the 520 will write faster thanks to its larger cache but in the long-run the 970 EVO Plus will out-write it. If the drive is fuller and hit with heavier workloads, the 970 EVO Plus will simply be more consistent. Please check the link in my signature for more.

As for random access: the SLC is a write cache (well, on current consumer drives), so small writes and latency will be good on both drives within that cache. The 970 EVO Plus's controller is more powerful so I would give it the edge. Outside of SLC, the 520 will tank because it hits the folding state. The 970 EVO Plus's hybrid SLC is much more consistent. But this is with random I/O outside SLC, if you get outside SLC.

For reads it's not really as big a deal, although I would generally give the nod to the 970 EVO Plus as they both use same-gen flash but the Plus's controller is faster. However when data is being folded it has a read latency penalty which will impact the 520 more if you get to that condition. Again, more likely if the drive is full, lots of writes, heavy workloads, etc.

You'll have to slog through my resources to understand the specifics. In my personal opinion it's not worth getting any of the current 4.0 drives unless they have specific features you need (although I think Samsung's drives also have these optional security features) or if they're priced right. If you can get the 970 EVO Plus significantly cheaper, let's say 10%, it's no contest in my mind.

edit for clarification: people will pull synthetic benchmarks out their butt to prove me wrong, that's fine. I'm talking the actual hardware and design here, over PCIe 3.0 specifically. You're not liable to notice a difference in these drives in most cases so usually go with the cheaper one, but if you have "traditional NVMe" tasks the 970 EVO Plus WILL beat the 520. It's as simple as that. The only place the 520 (and E16) shines is at 2TB.

 

[4EvrYng]

The only place the 520 (and E16) shines is at 2TB.

Thank you for your reply! Could you please elaborate on your "the only place the 520 (and E16) shines is at 2TB" statement? I am interested to hear as much as I can on it because it is 2TB models of both I am looking at.

 

[NewMaxx]

Thank you for your reply! Could you please elaborate on your "the only place the 520 (and E16) shines is at 2TB" statement? I am interested to hear as much as I can on it because it is 2TB models of both I am looking at.

2TB variants of older drives tended to perform worse than their 1TB counterparts. This would be any E12- or SM2262/EN-based drives, and also included the 970 EVO and SN750 for example. Various reasons for this but the primary one seemed to be the requirement of 512Gb/die flash at 64L (although I believe the earlier models used 256Gb and doubled dies per CE, with similar effect). When it comes to flash characteristics, you have a series of trade-offs so having higher density at the same layer count usually hurts performance.

This isn't the case with the 2TB E16 drives because they're using the newer 96L flash. Likewise I wouldn't expect this to hit the 970 EVO Plus either, although the EVO Plus is single-sided and only has two NAND packages which means 16DQ/HDQ. This is the maximum amount of dies per package and more dies/package does have issues, for example ODT (on-die termination) values, although in this context is just means the 970 EVO Plus is more expensive to manufacture most likely (but this has the benefit of the drive being single-sided at 2TB!). Now, many drives have moved to 96L flash, for example E12-based drives, and many have gone single-sided as well, however most have had a reduction in DRAM for this (512MB at 1/2TB) which is another shortcoming.

The tl;dr of this is that the 970 EVO Plus and E16 drives are the best at 2TB currently. As for caching, someone can correct me but I believe the 970 EVO Plus at 2TB has 6GB of static and 72GB of dynamic in comparison to 667GB of dynamic with the 520 for example. The problem is dynamic SLC takes up 3x TLC that must eventually be emptied and converted, that means 667GB of SLC = 2TB of TLC for example. Compare the E16 reference design here to the 970 EVO Plus and you'll see what I mean. So if you intend to have the drive full, perhaps doing prolonged writes, etc., the 970 EVO Plus is more consistent.

Of course I realized you asked about LQD and 4K specifically. Both drives are very fast there and you will be bottlenecked elsewhere on most consumer workloads. But nevertheless, they are faster at 2TB than other drives.

 

[4EvrYng]

The tl;dr of this is that the 970 EVO Plus and E16 drives are the best at 2TB currently. ...

I think I will go for Evo+. I’m planning on putting two of them in Win10 stripe. Now I need to decide should I get 1TB or 2TB model. Total cost makes 1TB attractive. Are you aware of any reason, please, why one should avoid 1TB one / favor 2TB one?

 

[NewMaxx]

The 2TB will have a larger SLC cache and might be slightly faster, plus of course double the TBW (based on capacity). However I wouldn't consider any of these to be important. Although if you're comparing 2x1TB to 1x2TB, the 1TB stripe will have a larger effective SLC cache with the same TBW and better maximum IOPS, with the obvious trade-offs of RAID-0 and using two NVMe drives.

 

[4EvrYng]

The 2TB will have a larger SLC cache and might be slightly faster, plus of course double the TBW (based on capacity). However I wouldn't consider any of these to be important. Although if you're comparing 2x1TB to 1x2TB, the 1TB stripe will have a larger effective SLC cache with the same TBW and better maximum IOPS, with the obvious trade-offs of RAID-0 and using two NVMe drives.

Thank you again!

 

[NewMaxx]

Thank you again!

Let us know how it goes!

 

[4EvrYng]

Let us know how it goes!

I will as soon as I do it Right now I am dealing with one issue with my current NVMe, more on that in separate thread soon ...

 

[Quartz121]

The 2TB will have a larger SLC cache and might be slightly faster, plus of course double the TBW (based on capacity). However I wouldn't consider any of these to be important. Although if you're comparing 2x1TB to 1x2TB, the 1TB stripe will have a larger effective SLC cache with the same TBW and better maximum IOPS, with the obvious trade-offs of RAID-0 and using two NVMe drives.

Sorry to bump this old thread, but I'm now facing the same choice dilemma with both drives still being roughly the same price. The system they'd go into does not allow for PCI-E 4.0 speeds, so that advantage of the 520 doesn't matter. I was going to go with the Samsung 970 2TB, but now I've also read that Samsung has done a stealth controller swap sometime last year on the 970 Evo Plus SSDs from a Phoenix to an Elpis: https://www.techspot.com/news/90998-samsung-swapping-parts-their-970-evo-plus-ssds.html

So now there are some high temperature issues with the new controller drives, and less consistency as the drive fills up. I don't know what to make of it, but one comment under this article states that they actually had problems with the original Phoenix controller too, suggesting that may have been a reason for the change:

skip741: "As an owner of the original 970 evo plus, I think I have an idea of why they changed the controller and the slc cache..Ive been in contact with samsung trying to get them to do a firmware update on these 970's for ages..The issue is that the slc cache was getting used up and was Not refreshing,thus users were experiencing a severe drop in write speeds to around 800mbs on these over time..it was as if the drive was writing at tlc speeds with little benefit of the superfast slc cache writes..the only way yo get the speed back was to do a secure erase which was an uber pain cuz you loose all data and have to redo everything ...even worse is that yes you can get the cache working again but its gonna go south in about a month of use..The 980 pro had the same issue..Owners bitched about it and samsung fixed it with an update..Not so for 970 plus owners..So I wonder if this redesign is in part motivated by those issues and an attempt to address them on a hardware level instead of a simple firmware update?..changing the controller makes sense and trippling the amount fo slc cache as well... maybe these New drives are more consistant in long term performance than the previous ones, becuz I can tell you, Im NOt pleased with that original controller and the way the slc cache works..its pretty bad and users get a sub par experience if they use the drive over time...some fix was and IS needed. "

There's no way to know which version of the 970 Evo 2TB I'd be getting when buying on-line, but I'm guessing chances are high it'd be the new Elpis controller version. So now I'm not sure if I should just get the Firecuda 520 2TB.

(I was looking at a 2TB SK Hynix P31 earlier, as I have and like the 1TB version in my main home desktop, but after recent-ish reports of those drives losing data after unexpected power losses, I decided it's not worth the risk. No problems with my home desktop so far, but then I also haven't had a sudden power loss yet. My high-end power supply has some semi-adequate hold-up time, not sure if that plays enough of a role.)

 

[Tech Junky]

The new WD SN770 works well and doesn't have the constraints of any of the previous mentioned drives and it's gen4 which resolved any potential bottlenecks in a gen3 slot. I use a couple of them at this point as secondary drives one in my TB4 enclosure to get 3GB/s from it and in the laptop it hits 3.5gb/s.

 

[john3850]

Only early Samsung 970 Evo Plus were fast they did something with the later ones.

 

[NewMaxx]

There's no way to know which version of the 970 Evo 2TB I'd be getting when buying on-line, but I'm guessing chances are high it'd be the new Elpis controller version. So now I'm not sure if I should just get the Firecuda 520 2TB.

At 2TB, the Elpis + 128L TLC would likely be superior to the original. This is because the original always had denser dies at 2TB. I'd actually argue the change is a side grade at worse with lower capacities. I could write a lot on this, but you should hit me up on my subreddit or my discord for more details. I would probably avoid the FireCuda 520 simply because it uses the Phison E16 controller, but I've covered this in recent sales threads on BAPCS (Reddit). The P31 is excellent, and I have covered the data on power loss issue also on my discord. I don't check or post here too often and would rather not go into deep detail.

 

[john3850]

NewMaxx that SSD Basics is one of better and useful articles that I came across.