Samsung investigating 840 EVO slowdowns
A couple of weeks ago we already reported that the Samsung 840 EVO SSDs are still experiencing slow read speeds with old data. basically TechReport placed a couple of SSDs on shelf, didn't use them. Then after three months they connected them again and boom, slow performance of the old data written.
The issue was supposedly fixed with a firmware update (EXT0CB6Q-firmware) issued in October, but some patched drives continue to exhibit the problem, including one of our own. Late Friday afternoon, Samsung issued the following statement on the matter:
In October, Samsung released a tool to address a slowdown in 840 EVO Sequential Read speeds reported by a small number of users after not using their drive for an extended period of time. This tool effectively and immediately returned the drive’s performance to normal levels. We understand that some users are experiencing the slowdown again. While we continue to look into the issue, Samsung will release an updated version of the Samsung SSD Magician software in March that will include a performance restoration tool.
If you look at the screenshot above you can see the performance degraded. This test unit 840 EVO SSD spent more than three months of the shelf, he results are pretty shocking: the months old data on the disk was only recoverable with an average read speed of 35.1MB/s.
After formatting the disk and loading it with new data the disk averaged 430MB/s in HD Tach, there's a abvious issue with long-term degradation of data stored in the triple-bit-per-cell memory.
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Well technically speaking was only meant to effect evo range, however am seeing slow down on my 840 pro in that ssd read speed tester bench.

Your 840 Pro is performing perfectly fine there, it's the average read speed figure that you want to look at - you're getting 540MB/s, so that's perfectly good, your 840 Pro isn't affected.
EDIT: sorry for 3 posts in a row, will multi-quote next time!
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Why go noob (evo), when you can go PRO ?

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Lol, yeah the only issue though, I installed the software, selected the run software option from the post install screen, at which point I assume it adds a task manager call, it inspected the drive and then promptly locked the computer up with zero response except to push the reset button.
So now I have a program installed that auto starts at boot and locks the computer up after it starts, you can see the issue here. This meant the only way I could disable it was to reboot in safe mode (a task which given how quickly Win 8 boots I was less than certain would work.) Luckily it did and I was able to uninstall the software.
the more i think about it maybe you have issues else where thats causing the software not to run as intended?
just a thought mind you.
Hmmm, I doubt it the system has been rock solid since it was first built and booted four months ago, zero issues, well a small issue with swapping Nvidia for an AMD card but that was resolved pretty quickly.
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My desktop is running a couple of 830s, but my laptop has the 840 evo. The speed restoration fix tool didn't like Intel's AHCI drivers, so I never ran it successfully. I think I'll just wait for the new Magician version in March the article was talking about. Considering how little I use my laptop, pretty much all data there is old. Yet no matter how little I use it, there's no forgiving such pitiful speed numbers.
I have to say this is very bad for Samsung's otherwise lucky SSD reputation of many years.
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Yeah loosing faith in Samsung over this. Firstly my 840 Evo, which hasn't been sitting idle for a few months is affected by this slow down issue, despite running the refresh tool and the firmware update prior to using it for the first time only 3 or 4 months ago. Second just tried to use their Magician Software, the only magic this piece of cr*p software could pull was to lock my computer up and render it utterly unuseable, a hard reset, boot and then it locks up again, I am assuming that the software has some sort of auto start option.
So yeah in to safe mode and removed that pile of rubbish and now the computer at least doesn't lock up anymore.
You can remove the auto start up function of Magician by removing that task from the Task Scheduler.