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SecondBreakfast

macrumors member
Original poster
Sep 13, 2014
33
15
Ok, guys, here's my dilemma:
I've got a mid-2011 27" iMac 3.1 with 20 gigs of RAM. I want to add a Samsung 850 SSD to speed everything up, but digging way into this thing makes me nervous. If I replace the SuperDrive with an SSD, it's not that involved, and the install would be a piece of cake; however, the optibay on these iMacs is only SATA2. Installing it via the 2nd SATA3 connector is a much more difficult job, and I'm not totally confident in my abilities.

So, what do you think? Is the extra speed worth the added headache? Or would I even notice the difference in speed? Thanks for the input, everyone!
 
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I have sata-2 ssd in a 2009 iMac and does not notice any difference in daily use compared to my 2014 Macbook air. Despite benchmark 250MB/s vs 750MB/s in read speed. It is because the search time is still very low and unless you copy big files, the read/write speed does not matter that much. That said I replaced the hard-drive and got a much quiter machine. Later tried to add a second ssd I had in spare in the optibay and couldn't get it stable. I think it was mostly because of the new ssd not being able to work right with my iMac. Because it wouldn't work right even at the hard-drive Bay, but putting it in my father's unibody 13" Macbook with sata-2 works without problems.
 
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I would add a second drive if I were you. Getting to the Superdrive in that machine, means you are already halfway there and the first part is really the most difficult. Then you just need to remove more screws and connectors, which you've already done, and pull out the motherboard, all of which is easy. Getting the motherboard back into place takes a bit of wiggling, but other than that, it is just a matter of going backwards and it really isn't that hard.

But in real life, no, I don't think you would see much of a difference.
 
It is better and much more efficient if you use the primary and secondary SATA connection (SATA0 & SATA1) for optimum results IMHO
 
I'd agree with the comments above. If you've made it far enough to get to removing the ODD and replacing with a SSD then the steps to get to the 2nd (unused) SATA port aren't that difficult. Take your time and keep a track of all the screws and you'll be fine. It's been a while since I did mine, but from what I remember the most difficult part is removing and refitting the screen as there are a few connectors you need to get at before pulling it away and putting it back. It also means you still have the ODD, which I do still use from time to time!
 
Well, looks like it's unanimous. I'll gather my courage, buy the kit from OWC, and do this up right. Thanks for all those who weighed in!
 
Well, looks like it's unanimous. I'll gather my courage, buy the kit from OWC, and do this up right. Thanks for all those who weighed in!

You also need to get a 2.5" to 3.5" hard drive bracket.

Also make sure to install that In-Line Digital Thermometer (from OWC kit) when upgrading.
 
Here's my setup. 2 units of old Samsung 840 series in RAID0 setup both fastened into the main storage bay. I just use this free apps SSD Fan Control and sets it to "Smart", no need to install that In-Line Digital Thermometer from OWC kit. Awesome results!
 

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Here's my setup. 2 units of old Samsung 840 series in RAID0 setup both fastened into the main storage bay. I just use this free apps SSD Fan Control and sets it to "Smart", no need to install that In-Line Digital Thermometer from OWC kit. Awesome results!
Love it! Clean and pretty
 
You can keep the superdrive and your old HD, just install it between the two with double sided tape that came with the OWC kit. I did this with my 27" 2010 iMac, and also installed the 850 evo. It really is a difference of night and day compared with the old HD. Just watch the video a couple of times and keep it running on an iPad or something when installing. Good luck!
 
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Unless your workflow is running benchmark, or keep copying large files etc. The high sequential speed usually is not that critical for normal user.

The main benefit of using SSD is the high IOPS. And then 850 cannot even saturate the SATA2 bandwidth (~250MB/s) on most of the random read / write job (just about 100MB/s). So, you should not able to feel any differences in normal OS operation (booting, loading apps, etc) by installing the SSD via SATA 2 or SATA 3.

So, if it's much easier to install via the SATA 2 port, just go for it.
 
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I agree. As soon as you have the iMac open you're pretty much done with all the hard part.

Once you make the connection to the extra SATA port, you can just put the SSD behind the optical drive. Once you put the OD back, the SSD won't move. So putting any kind of tape isn't necessary.
 
@SecondBreakfast, did you end up installing the SSD? How did it go?

I did the same thing earlier this year with my 2011 iMac. I bought a "kit" (really just a cable with a special connector and some double-sided foam tape) from OWC, and mounted the SSD against the back wall of the iMac, underneath the Superdrive. Used a SATA 3 connector that's on the back side of the logic board. The speed gain was incredible. I mean, really, it completely surprised me how awesome this old iMac suddenly became. It has a 3.4 GHz Core i7, so CPU was never the bottleneck. But even though I knew that, I was still completely blown away by it. It felt like a new-model machine.

I kept my 2TB mechanical drive in place (it was an upgrade done a couple years ago) and created a fusion drive so I wouldn't have to deal with two volumes, where to store data, backing up two drives, etc. I followed the guide on the Carbon Copy Cloner site, because it is one of the few guides that show how to install the recovery partition outside of the fused volumes (You install the recovery partition on the slowest drive, and then fuse the remaining space). The files you use most frequently get moved under the covers to the SSD, so after a few boots and launches, that old computer would boot up in like 15 seconds or less, and apps would launch almost immediately. And stuff like music and videos probably stayed on the mechanical drive, because speed isn't as important for those.
 
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