[SOLVED] Slow Write Speeds on Samsung 860 EVO

charles1971

Honorable
Mar 7, 2013
12
1
10,515
Hi,

My samsung 860 Evo 250gb (OS Installed) is underperforming in its write speeds. For sequential Read/Write its getting 560/330

330 mb/s is a lot lower than when I first got it. It is about 45% full and the test results are the same on various testing software.

Does anyone have any idea on why it is being so slow?

Thanks in advance

Edit: Drive health on various software is saying it is performing as expected
 
Last edited:
Solution
The fresh install option, I think it removed a fair few files as my SSD has dropped to 16 percent full.
Well it will be this as well as clearing up residual junk.

In effect the SSD has to write data to a block, and like sectors, these won't necessarily be entirely filled. And the SSD will always simply write to an empty block as this is the quickest.
So the more data you store, the longer it takes for the SSD to find the right data, and eventually the empty blocks become few and far between, so the SSD will have to wipe the data on the block before writing to it, which increases speeds once again.

Tie that up with residual junk files from downloads, software installs, cache, windows updates etc, and you have a slower SSD. But...

PC Tailor

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Hi,

My samsung 860 Evo 250gb (OS Installed) is underperforming in its write speeds. For sequential Read/Write its getting 560/330

330 mb/s is a lot lower than when I first got it. It is about 45% full and the test results are the same on various testing software.

Does anyone have any idea on why it is being so slow?

Thanks in advance

Edit: Drive health on various software is saying it is performing as expected
Are you encountering any issues in real time usage?
 

PC Tailor

Illustrious
Ambassador
Nothing noticable, it's just dropped from 560 ish when I first got it 5 months ago
Personally I would say if you're not encountering any real world issue, don't worry. Worrying about benchmarks can lead to a huge rabbit hole that leads to nothing!

Ultimately SSDs do slow down the more they are filled, and this is largely due to how NAND technology works.

You'll also want to ensure you have latest chipset drivers installed and Intel RST (if applicable) is up to date.
 

charles1971

Honorable
Mar 7, 2013
12
1
10,515
Personally I would say if you're not encountering any real world issue, don't worry. Worrying about benchmarks can lead to a huge rabbit hole that leads to nothing!

Ultimately SSDs do slow down the more they are filled, and this is largely due to how NAND technology works.

You'll also want to ensure you have latest chipset drivers installed and Intel RST (if applicable) is up to date.
I get what you're saying it's just more the fact I've not had it very long and it isn't even half full. Can't understand the sudden drop tbh, but thanks for your help :)
 

PC Tailor

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I fixed the issue it seems by refreshing windows through recovery. Does this mean that it was having slow write speeds as a result of being nearly half full?
Well a refresh doesn't remove files from my recollection.
Presumably more do to with residual junk files and no-trimming of the SSD causing read/write speeds to take longer because it's having to perform more operations to grab the data in question.
 

charles1971

Honorable
Mar 7, 2013
12
1
10,515
Well a refresh doesn't remove files from my recollection.
Presumably more do to with residual junk files and no-trimming of the SSD causing read/write speeds to take longer because it's having to perform more operations to grab the data in question.
The fresh install option, I think it removed a fair few files as my SSD has dropped to 16 percent full.
 

PC Tailor

Illustrious
Ambassador
The fresh install option, I think it removed a fair few files as my SSD has dropped to 16 percent full.
Well it will be this as well as clearing up residual junk.

In effect the SSD has to write data to a block, and like sectors, these won't necessarily be entirely filled. And the SSD will always simply write to an empty block as this is the quickest.
So the more data you store, the longer it takes for the SSD to find the right data, and eventually the empty blocks become few and far between, so the SSD will have to wipe the data on the block before writing to it, which increases speeds once again.

Tie that up with residual junk files from downloads, software installs, cache, windows updates etc, and you have a slower SSD. But again, if you don't encounter any real world issues, I wouldn't worry. Just keep storage to no more than 75% full as a rule of thumb.
 
Solution

charles1971

Honorable
Mar 7, 2013
12
1
10,515
Well it will be this as well as clearing up residual junk.

In effect the SSD has to write data to a block, and like sectors, these won't necessarily be entirely filled. And the SSD will always simply write to an empty block as this is the quickest.
So the more data you store, the longer it takes for the SSD to find the right data, and eventually the empty blocks become few and far between, so the SSD will have to wipe the data on the block before writing to it, which increases speeds once again.

Tie that up with residual junk files from downloads, software installs, cache, windows updates etc, and you have a slower SSD. But again, if you don't encounter any real world issues, I wouldn't worry. Just keep storage to no more than 75% full as a rule of thumb.
So now the sequential read/write speed of 560/530 is how it should be, and the drive should be working as normal?

Thank you for the help :)
 
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