PCIe 3.0 vs PCIe 4.0 NVMe SSD

[testcy]

is it worth it choosing and paying extra for a PCIe 4.0 SSD on a system that supports it instead of a PCI 3.0 SSD? Will there be a noticeable difference in speed overall or only in certain tasks like copying large files?

[filpo]

Just now, testcy said:

is it worth it choosing and paying extra for a PCIe 4.0 SSD on a system that supports it instead of a PCI 3.0 SSD?

no

 

Just now, testcy said:

Will there be a noticeable difference in speed overall or only in certain tasks like copying large files?

no, if your only gaming go for a gen 3 drive like the 970 evo plus/p3 

[testcy]

1 minute ago, filpo said:

no

 

no, if your only gaming go for a gen 3 drive like the 970 evo plus/p3 

And if not gaming?

[filpo]

Just now, testcy said:

And if not gaming?

depends. If you are doing large transfer files then even a 970 evo plus with dram cache is good enough

[testcy]

2 minutes ago, filpo said:

depends. If you are doing large transfer files then even a 970 evo plus with dram cache is good enough

What's the reason to buy a PCIe 4.0 NVMe SSD or even a 5.0 then?

[filpo]

Just now, testcy said:

What's the reason to buy a PCIe 4.0 NVMe SSD or even a 5.0 then?

Not much. Maybe a second or two in loading times for games and slightly faster file transfers but the differences in time are normally negligible (Though in REALLY big file transfers you might see the difference)

 

No reason to buy a 5.0 ssd as yes, they are faster but are also less reliable than pcie 4.0

[porina]

What is the price difference? Personally I'd aim to choose a good quality 4.0 SSD if I care at all about performance. The better 3.0 ones aren't really cheaper enough to make them interesting. However, if you're just looking at capacity over performance, then 3.0 and even SATA remains viable choices.

 

Even if supported, I wouldn't look at 5.0 mainly because it is still early in their lifecycle and they have room to mature. The premium isn't worth it.

[testcy]

14 minutes ago, porina said:

What is the price difference? Personally I'd aim to choose a good quality 4.0 SSD if I care at all about performance. The better 3.0 ones aren't really cheaper enough to make them interesting. However, if you're just looking at capacity over performance, then 3.0 and even SATA remains viable choices.

 

Even if supported, I wouldn't look at 5.0 mainly because it is still early in their lifecycle and they have room to mature. The premium isn't worth it.

PCIe 4.0 seems to be 25% more expensive than PCIe 3.0 for two SSDs I am considering.

[tkitch]

unless you're daily copying 10GB+ files a bunch of times between two different Gen 4 / gen 5 drives?

The added speed won't do shit.

 

Past a certain point "faster than hell" just means the computer can't keep up with it, and the REST of the computer is playing catchup with data access on the drive.

[Doobeedoo]

Depends what you do and expect from SSD as well as how down the line you plan to keep them. Also depends on prices at times.

[kokosnh]

Look on reviews 

https://www.tomshardware.com/reviews/kingston-kc3000-m2-ssd-review/2

the tasks that are bottlenecked by storage in meaningful way are few.

 

the top tire PCIe gen 4 SSD are fast, nobody is denying that ( 2-3 of NAND and Controllers generation newer then the PCIe 3.0 ones ),  it’s just that in everyday task, the storage is usually not the bottleneck.

 

but there are use case where the SSD will make the difference.  for me, the the price difference for top tire PCIe 3.0 and 4.0 is so small that I go for the PCIe 4.0

 

[cmndr]

Real world perception of speed is mainly limited by non-sequential, low queue depth operations. 
The peak speed during such operations is WELL bellow the max speed of PCIe 2.0. 

As a rule of thumb, nearly ANY SSD is "fast enough" for most use cases.

 

Getting a "good deal" will matter more than PCIe 4.0 vs 3.0. It might be worth $1-5 extra. 

I'd worry more about the controller on the SSD than the PCIe version though. Newer controllers are usually better. This often matches with PCIe generation but there are "mediocre" PCIe gen 4 products. 

[atxcyclist]

On 7/25/2023 at 9:35 AM, filpo said:

depends. If you are doing large transfer files then even a 970 evo plus with dram cache is good enough

I have been running a 2TB 970 Evo Plus in my gaming machine at home, they really are excellent drives, and for gaming load times are extremely minimal. I've found the jump from a SATA SSD to an NVMe one is tangible, but I've run PCIE 3.0x2, 3.0x4, and even 4.0 drives in machines and the storage speeds just don't become a factor in regular use like gaming.

[filpo]

1 minute ago, atxcyclist said:

but I've run PCIE 3.0x2, 3.0x4, and even 4.0 drives in machines and the storage speeds just don't become a factor in regular use like gaming

ye, the only reason I got a gen 4 drive was to see what it felt like (i had a sata ssd before) It was a jump but not amazingly noticeable as the ssd I had before also had dram cache

 

2 minutes ago, atxcyclist said:

but I've run PCIE 3.0x2, 3.0x4, and even 4.0 drives

pcie 4.0 only really shows it's shine in file transfers that are bigger than 50gb or even more

[NewMaxx]

4.0 drives have newer tech. That usually makes them the better bet if pricing is the same. Gen3 is starting to feel pretty outdated, aside from some of the very best drives (Gold P31, maybe 970EP, but even then). I'm not talking bandwidth. I mean latencies and low QD performance, power efficiency, etc.

[NobleGamer]

6 hours ago, NewMaxx said:

4.0 drives have newer tech. That usually makes them the better bet if pricing is the same.

So when pcie 4 budget drives (without cache) have the same pricing as some PCIE 3 with cache, I think there's a case to be made that the pcie 3 drives can deliver more consistent if not higher throughput, especially random read/writes. I think that is what keeps some people from going to 4.

 

One big example is: See 970 Evo Plus versus MP600 which is within $1 right now at 2TB, but there's more examples at 1TB.

 

6 hours ago, NewMaxx said:

I mean latencies and low QD performance, power efficiency, etc.

I'm curious: How big of a difference are the latencies? Wouldn't better low QD performance manifest in faster random throughput? What's your measure of power efficiency - mbps per milliwatt? I think people who care about pcie 3 over 4 are more concerned about heat & thus overall watt usage.

[NewMaxx]

2 hours ago, NobleGamer said:

So when pcie 4 budget drives (without cache) have the same pricing as some PCIE 3 with cache, I think there's a case to be made that the pcie 3 drives can deliver more consistent if not higher throughput, especially random read/writes. I think that is what keeps some people from going to 4.

 

One big example is: See 970 Evo Plus versus MP600 which is within $1 right now at 2TB, but there's more examples at 1TB.

 

I'm curious: How big of a difference are the latencies? Wouldn't better low QD performance manifest in faster random throughput? What's your measure of power efficiency - mbps per milliwatt? I think people who care about pcie 3 over 4 are more concerned about heat & thus overall watt usage.

The Gold P31 is good, mainly as it was designed to be Gen4 but they had trouble maintaining the interface and went with Gen3. 4-channel, DRAM, good controller, good flash. The original 970 EP isn't really equal as it's 8-channel, less efficient, older (less-efficient too) flash. However, Samsung had some issues producing that controller and used the 980 PRO's Elpis on newer 970EP's which was designed for their newer 128L flash as well, making it better, although the Gold P31 will probably still be better (Elpis will have a lower bus rate when restricted to a Gen3 interface but on the balance, Hynix's memory with PUC is more efficient; also, question of channel vs bus reduction for power savings).

 

A modern 12nm Gen4 controller that's DRAM-less will usually be ideal for consumer workloads. DRAM takes more power and there's not much that can really use the DRAM if the controller is fast enough, flash is fast enough, and SRAM + HMB is sufficient in size (very true of the SN770 for ex). Exception is with higher capacities - need more channels, more likely to have a heavier metadata load, or denser flash which is slower in-generation (e.g. 2TB SN770). Newer flash will usually have improved performance (incl latency) but not always, certainly 4KB random read QD1. Power efficiency is also better with newer flash (lower voltage, and architectural improvements), which translates to the drive when used in a Gen3 slot (in fact, will be more efficient).

 

Sustained writes - a more rare area of concern but I'd say newer drives have better SLC caching schemes, if anything. 970EP and Gold P31 have good hybrid designs, though. Improved SLC performance on newer designs is probably better for bursty consumer workloads. The 970EP being relegated to 8-channel really makes it a harder sell especially for laptops (where the Gold P31 shines) and SFF machines. Gold P31 is still hard to shake but is often not price-competitive or available in all markets. Oh, and power consumption (and efficiency) is directly related to heat production, ignoring the composite sensor readings. Current DRAM-less 4-channel controllers (IG5220/E21T/SM2269XT/MAP1602) with 176L+ flash (Micron, YMTC) will dominate any Gen3.

 

That being said, who needs it? If you can get older Gen3 tech at a good (better) price, go for it. It's an unfortunate truth that manufacturers put their new tech in higher Gen first (or back one Gen, Gen5/4 now). Hynix intended a design for Gen4 that ended up the Gold P31. The 970EP was updated in part due to factory failures and semiconductor costs. SATA SSDs? Good luck. I'd opt for a Gen4 drive at this juncture, unless you can get a deal/steal on Gen3. Every third party is subbing in random flash and controllers for Gen3 (and increasingly, Gen4). Disclaimer: not being aggressive here, just given my opinion and understanding.

 

(for example linked: MP600 Core XT is QLC, so is the NV2 as well for 2TB, one place the 970EP is still potentially solid is 2TB)

[testcy]

I asked about these elsewhere, but I would still like more opinions about Kioxia Exceria Plus G2 (PCIe 3.0) and ADATA XPG GAMMIX S70 BLADE (PCIe 4.0). Price difference is about 25%.

[AI_Must_Di3]

I would just add that if you plan on putting this device in your next build then it might be better to go with pci-e 4 instead so you can take advantage of it at that point. pci-e 3 was around for 10 years before they started changing over to pci-e 4. Just something to think about.