NVMe vs M.2

Avalon said:
860 is AHCI based SATA not NVMe, all the drives I referenced were obviously NVMe PCIe. As I mentioned an online retailer who offer same day delivery and you mentioned one that fits that description, if you look at the 2TB 660p pricing from them and then compare it to any main brand 2TB TLC drive you’ll see they are roughly twice the price, I haven’t looked at OCUK’s pricing recently, but they generally tend to be slightly higher with a similar metric.

You keep focusing on the type of cache, but ignoring that it’s less important than the size of cache. If the industry moved to MLC/TLC cache, that in itself will make little difference. A QLC drive is ‘fast’ if you stay in cache for writes, so as long as you are dumping under 76GB in one go to a relatively empty 500GB drive, you get full speed, as that scales up on a 2TB drive it becomes increasingly likely you won’t fill the cache. Reads will always be fast, so choose a drive with a large enough cache for your needs and you’re not going to notice the difference outside of synthetic benchmarks or doing something silly. Non of that will help a full write scenario though, which is where you went wrong.

As far as my pricing goes, I got cheap deals at the time, at least one other person got similar pricing on a 2TB 660p here, but pricing has generally gone up in recent months as the exchange rate has gone down, the % difference is still similar.
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On the contrary, the type of cache determines the size of the cache, if it was MLC you would have double the size of the cache.

Considering that the sustained write speed of the Samsung QLC flash is 80MB/s I think it's reasonable to compare against SATA drives.

When it comes to larger capacity drives, there is a somewhat bigger difference in price but not twice the price when comparing the same brands, the 2TB QVO is £210 and the EVO £270 for example. But larger drives aren't really economical when you can RAID 2x 1TB drives for less money and double the performance... I'm getting 1GB/s sustained write even on the oldé SATA interface.
 
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I ran out of space on 4TB of Mech HDD's (backlog of media to watch but will delete once viewed) so next step was logically (to me) 6-8TB but I wanted quietness now in my old age and 4TB SSD's are no go price wise now so that is why I bought 3x 2TB as a compromise I can work with for years and next time around it will be larger SSD's for less money hopefully.
 
Still confused about some of the prices that are being mentioned (these are all current as of today 13-Oct, all 2TB):

Non-QLC
Sabrent NVMe: £249
860 Evo NVMe: £299

QLC
Intel 660p NVMe: £197
Crucial MX500 SATA: £198
860 QVO SATA: £209
WD Blue SATA: £209

That's a pretty clear 25-50% premium of Non-QLC over QLC (where 25% is the "no-name" Sabrent, and 50% is Samsung).

Am I misunderstanding something (purely talking about price here)?
 
TLDR: If you write hundreds of GB/day and specifically more than 280GB of writes at once, QLC isn’t for you. If you don’t meet those criteria (that’s the overwhelming majority), then QLC will be indistinguishable from TLC in the real world.

You’re not comparing like with like, the Samsung 860 and other drives mentioned are AHCI and perform accordingly, the Samsung 9x0 series and Rocket are NVMe. The whole point here is NVMe QLC is indistinguishable in real world usage than TLC until you write more than the SLC cache, and in 2TB you need to be dumping 280GB in a single write operation before you’ll notice writes slow down (reads are always quick). The Rocket’s price is normally £329.99, at £249 it’s a bargain, it’s only slightly more than the £237.35 it briefly hit on September 12th. Today with those prices I would buy the Rocket. At £329 vs 197 if you don’t need to dump 280GB in one hit and aren’t doing so daily, then save £132, you are much more likely to notice that than the difference between TLC and QLC.

*Edit* As if by magic the price of the 660p was £16x yesterday from a well known source which made the Rocket almost exactly 50% more at 2TB and the Samsung almost 80% more, even if it’s AHCI and we should be comparing to the 970 which is still usually around £400 for 2TB.
 
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Avalon said:
TLDR: If you write hundreds of GB/day and specifically more than 280GB of writes at once, QLC isn’t for you. If you don’t meet those criteria (that’s the overwhelming majority), then QLC will be indistinguishable from TLC in the real world.

You’re not comparing like with like, the Samsung 860 and other drives mentioned are AHCI and perform accordingly, the Samsung 9x0 series and Rocket are NVMe. The whole point here is NVMe QLC is indistinguishable in real world usage than TLC until you write more than the SLC cache, and in 2TB you need to be dumping 280GB in a single write operation before you’ll notice writes slow down (reads are always quick). The Rocket’s price is normally £329.99, at £249 it’s a bargain, it’s only slightly more than the £237.35 it briefly hit on September 12th. Today with those prices I would buy the Rocket. At £329 vs 197 if you don’t need to dump 280GB in one hit and aren’t doing so daily, then save £132, you are much more likely to notice that than the difference between TLC and QLC.

*Edit* As if by magic the price of the 660p was £16x yesterday from a well known source which made the Rocket almost exactly 50% more at 2TB and the Samsung almost 80% more, even if it’s AHCI and we should be comparing to the 970 which is still usually around £400 for 2TB.
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In the real world, people don't work with empty drives.

TLC AHCI is superior in many aspects of performance to QLC NVMe. I'm seeing 850MB/s sustained write on my ancient 1TB EVO 850 array compared to the Intel 660p's 80MB/s, that's to say nothing of the durability...
 
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Avalon said:
*Edit* As if by magic the price of the 660p was £16x yesterday from a well known source which made the Rocket almost exactly 50% more at 2TB and the Samsung almost 80% more, even if it’s AHCI and we should be comparing to the 970 which is still usually around £400 for 2TB.
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I missed out on this deal!
 
Energize said:
In the real world, people don't work with empty drives.

TLC AHCI is superior in many aspects of performance to QLC NVMe. I'm seeing 850MB/s sustained write on my ancient 1TB EVO 850 array compared to the Intel 660p's 80MB/s, that's to say nothing of the durability...
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In the real world people dont exceed the SLC cache on a QLC drive regularly.

I'll regularly import large amounts of photos and have never hit the slow down.
 
Energize said:
Work with 50MB raw photos like I do and you hit it pretty quickly unfortunately.
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My toy camera only churns out 24MB RAW files. Still no problem however. Yes if you're moving 100s of GBs of photos regularly, and got fast cards and got a fast card reader then you probably can hit the cache limit. But then that much data on a regular basis you're going to want something MLC based purely for endurance.

For you QLC doesnt work, but for almost all the rest of the world it's going to be fine.
 
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With 1-4GB of DDR4 Ram Cache then an additional 48-78GB of Flash cache (1GB/2GB/4GB models) I highly doubt it will ever be problem, no sure why he like like a dog with a bone over this type of Flash memory, simply do not buy these products and instead buy a enterprise SSD that will have many time better Write Endurance and cost a few grand.

I have 860 PRO's and 860 QVO's BTW.
 
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b00merang69 said:
With 1-4GB of DDR4 Ram Cache then an additional 48-78GB of Flash cache (1GB/2GB/4GB models) I highly doubt it will ever be problem, no sure why he like like a dog with a bone over this type of Flash memory, simply do not buy these products and instead buy a enterprise SSD that will have many time better Write Endurance and cost a few grand.

I have 860 PRO's and 860 QVO's BTW.
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A dog with a bone because I simply raise the legitimate issue of QLC performance?

Suggesting an enterprise SSD is ridiculous, a cheap TLC SSD like the sabrent is able to keep a high sustained write speed suitable for importing large amounts of photo and video data, you don't need an enterprise SLC drive for that lol.
 
I never said you did but at least you would be happy with its TWB apart from the price and it was an attempt at sarcasm! ;)

In the meantime I will use my crappy poor-mans Flash based ones I got for about £140 each (£200 on Big River) for storage only (backed up to Ext Mech HDD's Raid 10) and in 2 years replace them with whatever is out.
 
Something I noticed since I installed my m.2, and I dont know if this is something that will happen on every machine as a enforced standard, or a bug or some other reason, but basically it seems on my board if a m.2 is in use then ASPM is forced to enabled. On my rig when this is enabled it will visibly slow down how quick window UI draws on the screen. With the m.2 drive in use, the bios setting for ASPM is ignored and its always turned on. ASPM on m.2 devices affects idle controller temperatures, so its plausible it would be forced on, but might be a bug.
 
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