Sunday, August 24th 2025

SK hynix Begins Mass Production of 321-Layer QLC NAND Flash

SK hynix Inc. announced today that it has completed development of its 321-layer 2 Tb QLC NAND flash product and has begun mass production. This achievement marks the world's first implementation of more than 300 layers using QLC technology, setting a new benchmark in NAND density. The company plans to release the product in the first half of next year following completion of global customer validation.

To maximize the cost competitiveness of its new product, SK hynix developed a 2 Tb device with double the capacity of existing solutions. To address potential performance degradation in large-capacity NAND, the company increased the number of planes, independent operation units within a chip, from 4 to 6. This enables greater parallel processing and significantly enhances simultaneous read performance.
As a result, the 321-layer QLC NAND delivers both higher capacity and improved performance compared to previous QLC products. Data transfer speed has doubled, write performance has improved by up to 56%, and read performance has improved by 18%. In addition, write power efficiency has increased by more than 23%, strengthening competitiveness in AI data centers where low power consumption is critical.

The company plans to apply its 321-layer NAND first to PC SSDs, before expanding to enterprise SSDs (eSSD) for data centers and UFS for smartphones. Leveraging its proprietary 32DP3 technology, which enables the simultaneous stacking of 32 NAND dies in a single package, SK hynix aims to enter the ultra-high-capacity eSSD market for AI servers by achieving twice the integration density.

"With the start of mass production, we have significantly strengthened our high-capacity product portfolio and secured cost competitiveness," said Jeong Woopyo, Head of NAND Development at SK hynix. "We will make a major leap forward as a full-stack AI memory provider, in line with the explosive growth in AI demand and high-performance requirements in the data center market."
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33 Comments on SK hynix Begins Mass Production of 321-Layer QLC NAND Flash

#1
JohH
I enjoy that it is 321 layers. 320 layers? Suboptimal. We can fit one more in there.
Posted on Reply
#2
azrael
The tech breakthrough no one wanted.
Posted on Reply
#3
Pepamami
I wonder if TLC one with less layers will be less expensive and has more endurance? And obviously less latency.

For a moment it feels like QLC creates a problem that no one asked for xd
Posted on Reply
#4
sudothelinuxwizard
Really, it's rather stupid that no one has made 4Tb dies yet, because pack eight of those puppies into a single package and you have a 4TB single sided 2230 SSD, or a consumer M.2 for the first time with four packages. Surely that must be possible with PLC though, right?
Posted on Reply
#5
The Tech Guy
PepamamiI wonder if TLC one with less layers will be less expensive and has more endurance? And obviously less latency.

For a moment it feels like QLC creates a problem that no one asked for xd
Intel and Micron developed a great technology called 3D XPoint. Unfortunately not enough adoption due to cost killed it off. I bought a Intel 800P back in 2019 and yes it was expensive per GB compared to the then current NVMe drives but today it still easily beats my Samsung 9100 Pro on a Gen 4 motherboard at RND4KQ1T1 (running Arch Linux, ext4) and it's only PCIe 3.0 x2.
Posted on Reply
#6
Bwaze
"The company plans to apply its 321-layer NAND first to PC SSDs, before expanding to enterprise SSDs (eSSD) for data centers and UFS for smartphones. Leveraging its proprietary 32DP3 technology, which enables the simultaneous stacking of 32 NAND dies in a single package, SK hynix aims to enter the ultra-high-capacity eSSD market for AI servers by achieving twice the integration density."

Why do I have the feeling they don't mean cheaper 8 TB and finally larger capacity internal drives for PC, but rather the same small up to 4 TB drives with better margins for them, and some brand new huge "lifestyle" external drives with stupidly high prices?

And the rest will go to "ultra-high-capacity eSSD market for AI servers by achieving twice the integration density"?

And also, they announced "mass production" before.

news.skhynix.com/sk-hynix-starts-mass-production-of-world-first-321-high-nand/
Posted on Reply
#7
Rowsol
I will never buy a QLC drive.
Posted on Reply
#8
TheLostSwede
News Editor
RowsolI will never buy a QLC drive.
I bet you're the guy that said this about TLC drives too...
At the moment, I agree with you, but we don't know what the future will bring.
Posted on Reply
#9
azrael
JohHI enjoy that it is 321 layers. 320 layers? Suboptimal. We can fit one more in there.
Actually, that's an indication of the longevity: Gone in 3... 2... 1...
Posted on Reply
#10
TheGeekn°72
JohHI enjoy that it is 321 layers. 320 layers? Suboptimal. We can fit one more in there.
I honestly wonder how do they define the final number in the design, like, did they jam pack as many layer as they could or was there a logical, scientific reason for it ?
azraelThe tech breakthrough no one wanted.
ah yes, *no body* wants tech to advance and improve, who could *possibly* want drives to contain more into smaller packages and improve efficiency, technological advancement is useless, amirite guys ?
sudothelinuxwizardReally, it's rather stupid that no one has made 4Tb dies yet, because pack eight of those puppies into a single package and you have a 4TB single sided 2230 SSD
this shit would cost an arm and a leg but I want to see it happen just because funni
sudothelinuxwizardor a consumer M.2 for the first time with four packages. Surely that must be possible with PLC though, right?
wdym with four packages ?
The Tech GuyIntel and Micron developed a great technology called 3D XPoint. Unfortunately not enough adoption due to cost killed it off. I bought a Intel 800P back in 2019 and yes it was expensive per GB compared to the then current NVMe drives but today it still easily beats my Samsung 9100 Pro on a Gen 4 motherboard at RND4KQ1T1 (running Arch Linux, ext4) and it's only PCIe 3.0 x2.
beats the 9100 Pro in latency ? (just asking to make sure that's what you meant, I'm not neck deep into SSD specs knowledge here)
BwazeWhy do I have the feeling they don't mean cheaper 8 TB and finally larger capacity internal drives for PC, but rather the same small up to 4 TB drives with better margins for them, and some brand new huge "lifestyle" external drives with stupidly high prices?
hear me out : SD-sized external storage makes a come back as hot swappable 2230 M.2s, tiny cartridge that looks like a gameboy game you slot into the side of your laptop and gets you the very best performance you could possibly get, that would be neat, probably stupid expensive but very neat
RowsolI will never buy a QLC drive.
that is one of the stupidest takes ever : I'm not saying you should buy one now, nor in the near future but don't say "never" because as tech progresses, older tech will get discontinued and the lower rung of the ladder will at some point be QLC and you'll be stuck with QLC saying next "I will never buy a #LC drive" instead
azraelActually, that's an indication of the longevity: Gone in 3... 2... 1...
are they that bad ?
Posted on Reply
#11
sudothelinuxwizard
TheGeekn°72wdym with four packages ?
Well, I meant to type 16TB, but I forgot (4x4TB packages is obviously 16TB)
Posted on Reply
#12
azrael
TheGeekn°72ah yes, *no body* wants tech to advance and improve, who could *possibly* want drives to contain more into smaller packages and improve efficiency, technological advancement is useless, amirite guys ?
So you're the person buying QLC drives? Maybe even eyeing PLC drives?

Well, to each their own...

And yes, QLC is *that* bad.
Posted on Reply
#13
sudothelinuxwizard
azraelAnd yes, QLC is *that* bad.
QLC is not bad, it is a good technology that is only priced poorly by greedy manufacturers, making it not worth it when TLC drives are so cheap. Remember when the QLC Intel 670p was like $35 for 2TB? That's what they ought to do with QLC, just make dirt cheap mass storage drives.
Posted on Reply
#14
TheGeekn°72
azraelSo you're the person buying QLC drives? Maybe even eyeing PLC drives?

Well, to each their own...

And yes, QLC is *that* bad.
I'm not saying I'd buy QLC drives if they're that bad, I'm saying that to make a pot, you need to start with a lump of clay
you ain't improving shit if you don't make the effort of trying to figure out how to do it
QLC is that bad, ok, but what about 10 years from now when the tech finally matures and gets good ?
how do you think CPUs moved from single core to multicore ? the first attempts at making multi core PCs was to use multiple CPUs, it was wildly expensive and didn't work super well, and yet look where we are now, Intel making 52c/52t consumer CPUs, AMD making 16c/32t across two dies with a buttload of cache on top, they didn't pull that out of their ass from nowhere...
Posted on Reply
#15
azrael
sudothelinuxwizardQLC is not bad, it is a good technology that is only priced poorly by greedy manufacturers, making it not worth it when TLC drives are so cheap. Remember when the QLC Intel 670p was like $35 for 2TB? That's what they ought to do with QLC, just make dirt cheap mass storage drives.
TheGeekn°72I'm not saying I'd buy QLC drives if they're that bad, I'm saying that to make a pot, you need to start with a lump of clay
you ain't improving shit if you don't make the effort of trying to figure out how to do it
QLC is that bad, ok, but what about 10 years from now when the tech finally matures and gets good ?
how do you think CPUs moved from single core to multicore ? the first attempts at making multi core PCs was to use multiple CPUs, it was wildly expensive and didn't work super well, and yet look where we are now, Intel making 52c/52t consumer CPUs, AMD making 16c/32t across two dies with a buttload of cache on top, they didn't pull that out of their ass from nowhere...
QLC is horrible. Not only are 16(!) different states in a single cell extremely difficult to handle, but the endurance of QLC cells is comically low. There's only so much that wear leveling and error correction can do. Here's a quick read on the subject.

Now, this *may* improve in the future (everything is possible), but I, for certain, wouldn't count on it.
Posted on Reply
#16
sudothelinuxwizard
azraelQLC is horrible. Not only are 16(!) different states in a single cell extremely difficult to handle, but the endurance of QLC cells is comically low. There's only so much that wear leveling and error correction can do. Here's a quick read on the subject.

Now, this *may* improve in the future (everything is possible), but I, for certain, wouldn't count on it.
I know about that. And you know what, I don't care. Better affordability of electronics is always a good thing, you need to stop dismissing products from your elitist "nothing but the best" viewpoint.

(Plus, please enlighten me what kind of normal user would even go through 5 TBW over the lifespan of an SSD, let alone the 80 of the absolute bottom barrel QLC 256GB SSDs. When you do nothing but use webapps, TBW does not matter one bit)
Posted on Reply
#17
Fourstaff
JohHI enjoy that it is 321 layers. 320 layers? Suboptimal. We can fit one more in there.
Lets add one more ... no one will notice ...
Posted on Reply
#18
Bwaze
FourstaffLets add one more ... no one will notice ...
Posted on Reply
#20
_roman_
sudothelinuxwizard4TB single sided 2230 SSD
I criticise any product which does not use the common M2 2280 format. AFAIK 22mm x 80 mm x heigth mm

People even defend the uncommon sizes. Only WLAN and mobile cards should be in the 2230 format (I strongly believe it is that size with different notches)

-- Still reading again another 1TB or 2TB m2 2280 nvme review.
Posted on Reply
#21
TheinsanegamerN
TheGeekn°72I'm not saying I'd buy QLC drives if they're that bad, I'm saying that to make a pot, you need to start with a lump of clay
you ain't improving shit if you don't make the effort of trying to figure out how to do it
QLC is that bad, ok, but what about 10 years from now when the tech finally matures and gets good ?
how do you think CPUs moved from single core to multicore ? the first attempts at making multi core PCs was to use multiple CPUs, it was wildly expensive and didn't work super well, and yet look where we are now, Intel making 52c/52t consumer CPUs, AMD making 16c/32t across two dies with a buttload of cache on top, they didn't pull that out of their ass from nowhere...
You can polish a turd for 10 years, it'll still be a turd. Sometimes, tech just doesnt work out. Like TSMC's 20nm tech. Or those multi core chips, the original multi core implementations were dropped for better tech. They didnt just keep at it trying to mature netburst style dual cores.

Instead, the backlash to QLC has lead to more improvements in TLC. Most premium drives still use TLC, because QLC is garbo. This did not happen with TLCs adoption, by this point in its life MLC has almost disappeared with one exception: the samsung pro drives.
Posted on Reply
#22
sudothelinuxwizard
_roman_I criticise any product which does not use the common M2 2280 format. AFAIK 22mm x 80 mm x heigth mm

People even defend the uncommon sizes. Only WLAN and mobile cards should be in the 2230 format (I strongly believe it is that size with different notches)

-- Still reading again another 1TB or 2TB m2 2280 nvme review.
Sure, but that won't stop manufacturers from cost-cutting, so we'll get 2230 SSDs anyway, so why not make them better?
Posted on Reply
#23
Philaphlous
Can't wait for the day that my main SSD on my laptop is 4TB... that'll feel so good...and it'll hopefully be dirt cheap thanks to SK Hynix....
Posted on Reply
#24
TheLostSwede
News Editor
azraelQLC is horrible. Not only are 16(!) different states in a single cell extremely difficult to handle, but the endurance of QLC cells is comically low. There's only so much that wear leveling and error correction can do. Here's a quick read on the subject.

Now, this *may* improve in the future (everything is possible), but I, for certain, wouldn't count on it.
How old is that article? Never trust an article that doesn't have a publication date for one.
The drives mentioned are 5+ years old, are you saying nothing has improved since then?
A lot of QLC drives are being used in the server space, especially for storage these days, so if they're as unreliable as you claim, how come large corporations are betting QLC drives?
_roman_I criticise any product which does not use the common M2 2280 format. AFAIK 22mm x 80 mm x heigth mm

People even defend the uncommon sizes. Only WLAN and mobile cards should be in the 2230 format (I strongly believe it is that size with different notches)

-- Still reading again another 1TB or 2TB m2 2280 nvme review.
Uhm... A lot of WiFi cards are 1630 and most 4G/5G cards are 3030 or 3042...

Posted on Reply
#25
EsaT
TheLostSwedeI bet you're the guy that said this about TLC drives too...
At the moment, I agree with you, but we don't know what the future will bring.
Original planar TLC using tiny transistors was indeed bad.
3D NAND bringing back bigger more robust transistors made it comparable to planar MLC.

Now what do we have left to fix QLC again pushing that edge?
Increasing transistor size back even further taking per cell data capacity gain back in increased silicon area consumption?
Posted on Reply
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