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Lets say you get the 1TB fusion, can you split the SSD side and use it? I was under the assumption the fusion software dictates this, Also, lets say your fusion drives HDD portion fails, can you still boot OSX if its loaded on the SSD or is the drive always considered one?

and if OSX determines what goes on fusion and what goes on SSD, is it constantly doing this, taking up ram or CPU usage slightly in the background processing? just some questions, Ive only been using OSX for 3 weeks now (only owned windows before).

Yes, absolutely you can split it up and created drives, one SSD and one HDD. That's what I'm planning on doing to my 3tb FD. Keep in mind if you get the 1TB you'll only have 24gb ssd to work with, a much better deal is the 2TB FD if you do decide to go for that.

If one part of your drive fails in a fusion setup then your whole drive fails. If you separate them then you will still have the other.

Yes it is indexing your files in the background but it is so little power that I doubt it will have any impact on your CPU or RAM usage.
 
Yes, absolutely you can split it up and created drives, one SSD and one HDD. That's what I'm planning on doing to my 3tb FD.
I was kicking that idea around myself, but overall, I'm pretty happy with how Fusion is working. I only have 500GB of the storage used up at the moment, but I'm not done fully setting up the computer.
 
I was kicking that idea around myself, but overall, I'm pretty happy with how Fusion is working. I only have 500GB of the storage used up at the moment, but I'm not done fully setting up the computer.

I think for most consumers the FD setup works great. But idiots like me who got the FD expecting to edit video off it are the ones who have to end up splitting it to tae advantage of the SSDs I/O.
 
For external USB drive, do you guys find the delay in accessing it annoying if it went to sleep?

I am using a WD my book duo in raid 1. It takes a few seconds to wake it up if it's sleeping.
 
For external USB drive, do you guys find the delay in accessing it annoying if it went to sleep?

I am using a WD my book duo in raid 1. It takes a few seconds to wake it up if it's sleeping.

Yes, absolutely. Which is why if you're going to have an external drive, it's best to have an SSD setup. I think the most superior one is SSD to Thunderbolt which gives you the best input/output speeds and lowest latency.
 
For external USB drive, do you guys find the delay in accessing it annoying if it went to sleep?
I have a TB external drive that was holding my data for the MBP, and I didn't find the delay to be too annoying with that. Now that I have a 2TB Fusion drive in my iMac, the external drive is solely used for Time Machine
 
I am also using a 2tb sub drive for time machine. But no matter how it's connected.. I occasionally get 'disk ejection error'. Usually when the iMac wakes from sleep

Is it the disk? It's a WD disk in a generic enclosure. I switched to a sea gate expansion 5tb yesterday. Haven't had the same problem so far.
 
Its it really any advantage of splitting the fusion drive? I have the 2tb and would like to try it if there's a good benefit.
 
Its it really any advantage of splitting the fusion drive? I have the 2tb and would like to try it if there's a good benefit.

I'm probably going to split my Fusion drive when my new iMac arrives. The advantage is that the SSD part of the fusion drive uses a PCI-Express interface rather than an SATA3 interface which most HDD and SSD drives use. The difference is that PCI-Express Read/Write speeds are significantly faster (I've seen tests showing around 2000MB/s) than SSD drives with SATA3 interface (Usually around 500MB/s).

So the advantage of splitting is that if you put your OS on the PCIe SSD drive, your OS will boot much faster and apps will load faster than even SATA3 SSD drives.

The other key advantage for me is that I can partition the PCIe SSD and put Windows 10 on it, which you can't do with Fusion Drive as Windows doesn't recognise the Fusion Drive set-up so runs entirely off the HDD.

I bought a 1TB Samsung EVO 850 SSD to replace the HDD drive and will split the fusion drive to put the OS on the PCIe SDD and use the 1TB SSD for the rest of the apps and stuff I don't use as much. I've also amassed a stack of External HDDs which I think I'll put in a RAID 0 Enclosure and use for storage.

Does anyone have any experience with splitting a fusion drive? Are there any bugs or OS quirks that result from doing so?
 
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Does anyone have any experience with splitting a fusion drive? Are there any bugs or OS quirks that result from doing so?
Yes, I have split the Fusion Drive on a late 2012 iMac (the HDD failed). And it works perfectly fine. The only difference is that the OS now sees two drives as individual drives instead of one drive.

I bought a 1TB Samsung EVO 850 SSD to replace the HDD drive and will split the fusion drive to put the OS on the PCIe SDD and use the 1TB SSD for the rest of the apps and stuff I don't use as much. I've also amassed a stack of External HDDs which I think I'll put in a RAID 0 Enclosure and use for storage.
Are you planning on opening the iMac to replace the HDD with the SSD, or run the SSD externally?
 
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Yes, I have split the Fusion Drive on a late 2012 iMac (the HDD failed). And it works perfectly fine. The only difference is that the OS now sees two drives as individual drives instead of one drive.

Are you planning on opening the iMac to replace the HDD with the SSD, or run the SSD externally?

Thanks for the feedback on your experience.

I'm a bit undecided really. From what I understand using the SSD on a USB3 cable won't cause a significant drop in disk performance and I can also keep my iMac intact and preserve my 2 year warranty that way. However, looking at the iFixit guide, you can buy replacement adhesive to reseal the iMac back to its factory state after performing a bit of surgery, so I might go ahead and do that. I haven't totally decided.

I might also just give Fusion Drive a go and see how I get on with it. It might be just fine. The only concern is using windows 10 on Bootcamp, but having said that I've always had Windows on a 7200rpm drive so it's not going to make a big difference to continue this way.

I think I'll decide when the new iMac arrives. I've got until 31 Jan to refund the SSD if I decide I can live without it.
 
The only issue with using USB3 for an SSD is the lack of TRIM support, which is offered through Thunderbolt. And yes, you reseal the iMac (I have done that too on the aforementioned iMac). It not not easy aligning the screen with the body, but with a lot of patience and persistence it is possible.

Since you got the Fusion Drive and not SSD you might as well try out and see how you like it. And if you are worried about Windows you can always install that on your external SSD.
 
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The only issue with using USB3 for an SSD is the lack of TRIM support, which is offered through Thunderbolt. And yes, you reseal the iMac (I have done that too on the aforementioned iMac). It not not easy aligning the screen with the body, but with a lot of patience and persistence it is possible.

Since you got the Fusion Drive and not SSD you might as well try out and see how you like it. And if you are worried about Windows you can always install that on your external SSD.

Ah yes I hadn't thought about TRIM support for the SSD. Can I get around that with software or does it just not work on USB 3?

If not then I might end up just sending the SSD back to Amazon.
 
AFAIK there is no way to work around that. The TRIM command happens at the OS level and the connection needs to support it, which Thunderbolt does because the connection is straight to the CPU.
 
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Its it really any advantage of splitting the fusion drive? I have the 2tb and would like to try it if there's a good benefit.
Well I suppose the advantage is you dictate what goes on the flash portion and not OS X. Plus you can then install windows on the flash instead of being forced to do that on the spinning disk.

I debated this a couple of times, but I like the simplicity of Fusion and so far its been fast for me.
 
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