-- By starting with the same MLC flash memory used in mainstream SSDs instead of the niche product that is SLC NAND
some background on this statement? last I knew, all NAND (on a given node, etc.) was the same, SLC/MLC/TLC being a figment of the controller's imagination.
Can be either way. This is completely up to the manufacturer on a case by case basis. It's cheaper to design and build one piece of silicon, so that's the starting point and there needs to be technically compelling reasons to make custom silicon for the SLC and MLC parts.
SLC, MLC, and TLC are all different in hardware, not merely software. The controller can take MLC and TLC and treat them similarly to SLC by ignoring the second bit in MLC and both the second and third bit in TLC for each cell. This is not a perfect replacement for SLC, but it means that Transcend can buy standard MLC NAND chips instead of getting SLC chips custom-made.
This is better for performance and reliability granted at the cost of half the capacity, because it is easier to write to the first level of a NAND memory cell than the second or third levels. With TLC, writing to the third level is so difficult that it's avoided when at all possible and TLC needs very powerful error correction for when writing to that third cell is necessary to at least somewhat ensure data integrity.
The difference is the manufacturer choosing to configure, qualify and sell a specific SLC device or not, which can be the same physical piece of silicon with special configuration or might be a different silicon design altogether. In this case, transcend is making the choice to either use the "SLC mode" of the MLC part or skip to addresses that make up the 2nd bit of the flash cell and leave only the first bit programmed. In theory, that first bit programmed has higher reliability if left that way.
MLC and TLC were created to increase density as there was diminishing returns when shrinking the die process for flash memory. After sufficient generations, it is now cheap enough to waste 1/2 or even 2/3 of the usable memory to gain speed. SLC costs too much to pump out, while MLC and TLC are flooding the market, so being able to use these commodities for double duty will be great.
This should work out well to reinvigorate the stagnant sector as people are willing to pay double for an 850Pro and triple for a 950Pro. Maybe samsung will finally have some competition in the high end sector.
Well, you're right, I am basing my bias on experience, and it is in regards to their consumer-class products, specifically flash drives and consumer SSD's. I've had a 16GB flash drive fail and seen an SSD lock itself (Sandforce 2281-based SSD370) and no longer detect in BIOS, but both could have been localized incidences. But that's in stark contrast to Sandisk, Crucial/Micron/Lexar products where I've never seen a failure.
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FunBunny2 - Thursday, December 31, 2015 - link
-- By starting with the same MLC flash memory used in mainstream SSDs instead of the niche product that is SLC NANDsome background on this statement? last I knew, all NAND (on a given node, etc.) was the same, SLC/MLC/TLC being a figment of the controller's imagination.
menting - Thursday, December 31, 2015 - link
no..that's not true. SLC/MLC/TLC are definitely different as far as chip layout goes.woggs - Thursday, December 31, 2015 - link
Can be either way. This is completely up to the manufacturer on a case by case basis. It's cheaper to design and build one piece of silicon, so that's the starting point and there needs to be technically compelling reasons to make custom silicon for the SLC and MLC parts.Blazorthon - Sunday, January 3, 2016 - link
SLC, MLC, and TLC are all different in hardware, not merely software. The controller can take MLC and TLC and treat them similarly to SLC by ignoring the second bit in MLC and both the second and third bit in TLC for each cell. This is not a perfect replacement for SLC, but it means that Transcend can buy standard MLC NAND chips instead of getting SLC chips custom-made.This is better for performance and reliability granted at the cost of half the capacity, because it is easier to write to the first level of a NAND memory cell than the second or third levels. With TLC, writing to the third level is so difficult that it's avoided when at all possible and TLC needs very powerful error correction for when writing to that third cell is necessary to at least somewhat ensure data integrity.
woggs - Thursday, December 31, 2015 - link
The difference is the manufacturer choosing to configure, qualify and sell a specific SLC device or not, which can be the same physical piece of silicon with special configuration or might be a different silicon design altogether. In this case, transcend is making the choice to either use the "SLC mode" of the MLC part or skip to addresses that make up the 2nd bit of the flash cell and leave only the first bit programmed. In theory, that first bit programmed has higher reliability if left that way.Byte - Sunday, January 3, 2016 - link
MLC and TLC were created to increase density as there was diminishing returns when shrinking the die process for flash memory. After sufficient generations, it is now cheap enough to waste 1/2 or even 2/3 of the usable memory to gain speed. SLC costs too much to pump out, while MLC and TLC are flooding the market, so being able to use these commodities for double duty will be great.This should work out well to reinvigorate the stagnant sector as people are willing to pay double for an 850Pro and triple for a 950Pro. Maybe samsung will finally have some competition in the high end sector.
Samus - Thursday, December 31, 2015 - link
I have a hard time justifying Transcend and "Industrial" in the same sentence.smilingcrow - Thursday, December 31, 2015 - link
Open your mind and transcend its limitations.extide - Thursday, December 31, 2015 - link
Sounds like a personal problem to me, they are used in a LOT of stuff!Samus - Saturday, January 2, 2016 - link
Well, you're right, I am basing my bias on experience, and it is in regards to their consumer-class products, specifically flash drives and consumer SSD's. I've had a 16GB flash drive fail and seen an SSD lock itself (Sandforce 2281-based SSD370) and no longer detect in BIOS, but both could have been localized incidences. But that's in stark contrast to Sandisk, Crucial/Micron/Lexar products where I've never seen a failure.haukionkannel - Saturday, January 2, 2016 - link
With that kind of endurance They can easily offer long varrant and that with encryption and safe circuit against electricity spikes means a lot!ddriver - Friday, January 1, 2016 - link
Can I buy it with pseudo dollars?NewerTech - Sunday, January 3, 2016 - link
Yes, if you are pseudo-buying.jabber - Friday, January 1, 2016 - link
I'll get a 2240 M.2 one for my Chromebook next year.