Strange. I had that two and it didn’t bother me as the boot drive always remained hidden…………..until the upgrade to El Cap that is.
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Has anyone tried the OWC Accelsior S?
- Thread starter steffi
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On 10.9.5, by all means get TRIM Enabler or it's bigger brother Disk Sensei! I'm assuming you know that in Yosemite (10.10.4 or above) and El Cap you don't need it to enable TRIM because you can enable it in Terminal.
However, Disk Sensei has other house keeping functions you might appreciate.
Lou
I just purchased an OWC Accelsior S and I'm really underwhelmed. I'm getting 50-70 MB/s Write Speed using a Sandisk SSD Plus. When that drive was connected via the stock SATA connectors on my 2010 Mac Pro I was getting 120 MB/s. Is there something I should know?
I am running Sierra, 12 Core Mac Pro, 3.46ghz.
I am running Sierra, 12 Core Mac Pro, 3.46ghz.
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I've got one too (Accelsior S), and the speed has been as promised. Do you have TRIM enabled on your SSD? If not, then the writes to SSD will eventually suffer a lot. SSD cells/blocks have to be emptied before they can be written to. SSD does this emptying at the time when the TRIM function tells them to do so, and when it is ok to do so.
You might want to tick trim function on (terminal: sudo trimforce enable), and then find a way to manually trim all SSD blocks. There are graphical software and there was another way to do it. It might have been the single user mode and fsck -fy. Please verify this last one from google/internet before trying.
You should get your SSD write speeds up.
You might want to tick trim function on (terminal: sudo trimforce enable), and then find a way to manually trim all SSD blocks. There are graphical software and there was another way to do it. It might have been the single user mode and fsck -fy. Please verify this last one from google/internet before trying.
You should get your SSD write speeds up.
I did go to terminal and type sudo trimforce enable. but that didn't change anything.
[doublepost=1509563781][/doublepost]Update, so I moved the accelsior from PCI slot 2 to Slot 3, and the ran SUDO TRIMFORCE enable again and now I am getting much better speeds.
[doublepost=1509563781][/doublepost]Update, so I moved the accelsior from PCI slot 2 to Slot 3, and the ran SUDO TRIMFORCE enable again and now I am getting much better speeds.
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You can check if trim is activated from Apple menu under about this Mac, system report. Select SATA/SATA Express, your SSD, and check for TRIM support: YES (or NO).
You will need to manually run the TRIM to the hole SSD before all cells/blocks are TRIM:ed again. It seems (googled it) that the single user mode and fsck -fy will do the trick. Personally I have used Cindori's Disk Sensei (about 10-15€ or so) to do that.
You will need to manually run the TRIM to the hole SSD before all cells/blocks are TRIM:ed again. It seems (googled it) that the single user mode and fsck -fy will do the trick. Personally I have used Cindori's Disk Sensei (about 10-15€ or so) to do that.
I have two of the Accelsior S cards, both with Samsung 850Pro 500gig ssd.
One is in my 2012 MP 5,1, and the other is in my flashed 2009 MP 4,1.
Both cards work perfectly for macOS in ElCap, Sierra, and High Sierra.
I'm very happy with them, and for what do, which is let you use 2.5inch sata3 SSD's at full speed, they are great.
One is in my 2012 MP 5,1, and the other is in my flashed 2009 MP 4,1.
Both cards work perfectly for macOS in ElCap, Sierra, and High Sierra.
I'm very happy with them, and for what do, which is let you use 2.5inch sata3 SSD's at full speed, they are great.
That's great to see.
Though now we have been left with a suspect that it was dependent on the slot. But if it was not the slot, then
probably what could have happened, is that the disk test wrote many cells and blocks, then marked them empty, and TRIM told SSD to do the trim-trick. After that the writes are again at full speed to trimmed cells again.
Average figures seem to be quite ok now for Sandisk plus models. Specs are allmost always given with those "up-to" figures.
Today I benchmarked the ssd speed of my Samsung 850 mounted on an OWC Accelsior S under El Capitan. It was slow (70 Mb/s). Booting in the singe user mode and running fsck -fy solved the problem for a short time, but then the writing speed became slow again. I checked about this Mac Trim > SATA > support: No.
Don 't the Samsung and the other SSD Neptune OWC installed in drive bay 2 support TRIM? Or is it save to enable it with the terminal command sudo trimforce? And will this be enabled when I boot from another partition (Sierra on the Neptune OWC SSD?)
Don 't the Samsung and the other SSD Neptune OWC installed in drive bay 2 support TRIM? Or is it save to enable it with the terminal command sudo trimforce? And will this be enabled when I boot from another partition (Sierra on the Neptune OWC SSD?)
It might be a fault with the Samsung driver with that particular type of SSD.
The driver software could be incompatible with Apple trim today.
Who to blame for this - I don't know.
edit. you must have ment 70 MBps. Because 70 Mbps is not a good speed for anything modern media transfer speed.
The driver software could be incompatible with Apple trim today.
Who to blame for this - I don't know.
edit. you must have ment 70 MBps. Because 70 Mbps is not a good speed for anything modern media transfer speed.
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Did you try to enable TRIM yourself? It is not self enabling except with an SSD identified as an Apple device.
I am running five Samsung SSDs. One SM 951 and four 840 devices. All have TRIM enabled. Two are mounted on the SATA bus. The other three are on PCIE cards. Attached are my write/read speed readings. The first is an 840 on the SATA Bus. The second is an 840 on a Velocity x2 PCIe card.
Note: You may have guessed from some of my previous posts, that I am no fan of OWC.
Lou
What brand of PCI card do you recommend. I have a 2009 MP flashed converted to 5,1 Thanks
Well OWC is pushing the Accelsior S for 50 bucks. So my plan is to get either that one or another choice and mount a 1TB SSD on it in my 2009 MP which is now a 5,1 and I plan on adding up to 24GB ram.
I could enable TRIM in the terminal on my first MacPro and now I have much better writing speeds on my Samsung installed on a OWC Accelsior SATA III pci card. A pleasant surprise.
However on my second computer I also have a Accelsior PCI-e SSD (two blades in RAID) and this card doesn't support TRIM. There the writing speeds dropped from 550 to 70 MBps.
However on my second computer I also have a Accelsior PCI-e SSD (two blades in RAID) and this card doesn't support TRIM. There the writing speeds dropped from 550 to 70 MBps.
Your plan sounds good to me. I won't recommend OWC in general, but for this PCIe SATA III card, and OWC sell it for $50. I can't see why not going for this option, unless you want a card that can boot Windows.
No I'm on a Mac an old one as I said. What is the most fool proof way to do a TRIM when I get the new SSD on my old Mac? Thanks
1) Open Terminal
2) Enter
Code:
sudo trimforce enableYou can actually do it now, no need to wait until you get the SSD.
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If you're on 10.10.4 or newer.
For older OS's you could patch IOAHCIBlockStorage through terminal (google it) or use something like this little app.
If you're on 10.10.4 or newer.
For older OS's you could patch IOAHCIBlockStorage through terminal (google it) or use something like this little app.
I'm running 10.11.6 it won't let me download the app but since I'm on 10.11.6 then how do I do it? Thanks
You have to be logged in to download from insanelymac, but since you're on El Capitan just do what @h9826790 wrote in his post - sudo trimforce enable.
Thanks I was told years ago when you enter sudo in the terminal you have to be careful bad things could happen?