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memo06dic

macrumors newbie
Original poster
Jul 26, 2005
22
1
Hi, I am planning on replacing my 1TB Fusion Drive with a 2.5" internal 250GB Samsung 850 EVO SSD. After the installation I plan to use the 32GB SSD portion as a scratch disk.

Do I need to 'unfuse' my Fusion Drive before removing the HDD?
 
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Hi, I am planning on replacing my 1TB Fusion Drive with a 2.5" internal 250GB Samsung 850 EVO SSD. After the installation I plan to use the 32GB SSD portion as a scratch disk.

Do I need to 'unfuse' my Fusion Drive before removing the HDD?

Yes you need to un-fuse first. Keep in mind, that if you do the replacement and need to have the machine repaired under warranty, Apple may remove the 3rd party hardware and replace it with Apple approved hardware.
 
It doesn't make sense to tear open a brand-new iMac and replace the SATA HDD with an SSD.

The fusion drive that is in there will probably benchmark FASTER.

Even though it's 32gb, the SSD/flash portion of the fusion is VERY fast, several times faster than any SATA SDD will be.

Run Blackmagic Speed Test on your current setup and post the results here.
 
It doesn't make sense to tear open a brand-new iMac and replace the SATA HDD with an SSD.

The fusion drive that is in there will probably benchmark FASTER.

Even though it's 32gb, the SSD/flash portion of the fusion is VERY fast, several times faster than any SATA SDD will be.

Run Blackmagic Speed Test on your current setup and post the results here.

That depends entirely on the OP’s use case. But yes, it’s a very good idea to do some benchmarking to establish a baseline before making any changes to the setup. These benchmarks may also serve as a guideline to whether a change would be beneficial at all.
 
It doesn't make sense to tear open a brand-new iMac and replace the SATA HDD with an SSD.

The fusion drive that is in there will probably benchmark FASTER.

Even though it's 32gb, the SSD/flash portion of the fusion is VERY fast, several times faster than any SATA SDD will be.

Run Blackmagic Speed Test on your current setup and post the results here.


Interesting. I am about to order an iMac to replace my 2006 Mac Pro and was thinking to choose a 128 or 256 GB SSD storage instead of a Fusion Drive. I hope to see someone run Blackmagic speed tests.
 
I agree with member "Fishrrman", and not just only for the reasons he stated but also considering that the OP will void his warranty and the difficulty of opening up a glued together iMac! Best to leave well enough alone. The old adage goes here... if it's not broke.....
 
I wouldn't open up a new iMac. Enjoy it for a few years and upgrade the drive in 4–5 yrs. I am using 2TB Fusion Drive now and it's plenty fast for daily use and some 4K video edits/exporting.

For storage of media, it's silly to use SSD. Also, the limitations may be with the SATA port form the Fusion Drive so SSD may not be that much faster.
 
So if you accidently bought the fusion drive, I'm so sorry. It's crap. The 1tb is especially slow. I've had two macs that I bought that were crap slow and I returned them. I got the SSD drive and it's flawless. To be honest, if you are past the return period it might be worth going to apple or an authorized repair shop and having them install it. I would be miserable with the fusion drive (was). Maybe sell on craigslist and buy a new iMac with SSD?
 
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So if you accidently bought the fusion drive, I'm so sorry. It's crap. The 1tb is especially slow. I've had two macs that I bought that were crap slow and I returned them. I got the fusion drive and it's flawless. To be honest, if you are past the return period it might be worth going to apple or an authorized repair shop and having them install it. I would be miserable with the fusion drive (was). Maybe sell on craigslist and buy a new iMac with SSD?
hmmm... Which is it? "crap", or flawless?
As was already mentioned in this thread - your experience with a fusion drive depends on how you like to work. Fusion drive is quite acceptable to most users, but it's not for everybody. That would be one reason why Apple has other options available, eh?
 
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hmmm... Which is it? "crap", or flawless?
As was already mentioned in this thread - your experience with a fusion drive depends on how you like to work. Fusion drive is quite acceptable to most users, but it's not for everybody. That would be one reason why Apple has other options available, eh?
Just updated my post, meant SSD.
[doublepost=1502293061][/doublepost]
Which iMac and for what usage?
I would recommend the poster sell his imac rather than keep it. And purchase a new one with SSD. I wouldn't put an external SSD to the mac (the speed increase is negligible compared to an SSD). The fusion drive is a failure on Apple's part. I have many posts here discussing the fusion drive and it's lack of performance. The very first hardware upgrade to consider when buying an iMac is the hard drive. Get the SSD. The performance is read/write speeds from 400-500 on fusion drive to 2k+ speeds on SSD. Fusion drives are the first piece of hardware the will slow down your mac.

An i7 processor upgrade with a 1tb fusion drive shouldn't even be an available option. The fusion drive will negate the i7 upgrade.
 
I successfully replaced the hdd part of the 1TB fussion drive with a 250GB SSD.

The fussion drive was ok, but from past experiences, I knew my iMac would run faster with a sata ssd.

This was my first time opening the glued display. I bough 32GB of ram from owc and they sent me all the tools and the double sided tape needed to re assemble my 21.5" iMac. It took me around 4 hours to complete the ram and ssd upgrade.

I know the build to order ssd is much faster but I live in Mexico and here you can buy stock models and pay them in 24 months without any interests. BTO Macs don't have this 0% APR.
[doublepost=1502328187][/doublepost]For those who asked for benchmarks, I'm sorry I don't have screenshots. With the 1TB fussion drive I had read speeds varying from 90MB/s to 1200MB/s and write speeds from 80MB/s to 800MB/s.

Now I have constant read and write speeds of 450MB/s on my startup sata ssd and 800MB/s write and 1200 read speeds on my 28GB unfused ssd.
 
I successfully replaced the hdd part of the 1TB fussion drive with a 250GB SSD.

The fussion drive was ok, but from past experiences, I knew my iMac would run faster with a sata ssd.

This was my first time opening the glued display. I bough 32GB of ram from owc and they sent me all the tools and the double sided tape needed to re assemble my 21.5" iMac. It took me around 4 hours to complete the ram and ssd upgrade.

I know the build to order ssd is much faster but I live in Mexico and here you can buy stock models and pay them in 24 months without any interests. BTO Macs don't have this 0% APR.
[doublepost=1502328187][/doublepost]For those who asked for benchmarks, I'm sorry I don't have screenshots. With the 1TB fussion drive I had read speeds varying from 90MB/s to 1200MB/s and write speeds from 80MB/s to 800MB/s.

Now I have constant read and write speeds of 450MB/s on my startup sata ssd and 800MB/s write and 1200 read speeds on my 28GB unfused ssd.

Why not fuse the PCIe 28GB drive with the SATA 250GB SSD? You get one drive recognized by the system, and the OS manages the more frequently used data onto the faster of the two drives, so your boot/OS disk would be even faster than it is now.
 
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[doublepost=1502328187][/doublepost]For those who asked for benchmarks, I'm sorry I don't have screenshots. With the 1TB fussion drive I had read speeds varying from 90MB/s to 1200MB/s and write speeds from 80MB/s to 800MB/s.

Now I have constant read and write speeds of 450MB/s on my startup sata ssd and 800MB/s write and 1200 read speeds on my 28GB unfused ssd.

Hum, I don't understand why you don't have read and write speeds that I have. I used black magic on my ssd and I'm getting 1850 write and 2300 read mb/s. :?
 
just get a SSUBX replacement part off ebay and the whole setup will fly. Steer away from SSUAX parts, they're only 2channel.

If you find SSUBX parts too expensive, an 850EVO will still sustain 500+ MB/s (much lower than ~2000MB/s that an SSUBX will do), but miles ahead of 7200rpm platters.

Don't know what price SSUBX are going for in the US, but you might save some $ via DYI upgrade rather than BTO-ing it with the same SSUBX factory installed...or not...for example in my country it's 200$ cheaper to buy a 1TB SSUBX and DYI upgrade it than BTO-ing it from Apple. In the US i see the 1TB SSD is 700$, whereas on ebay they go for at least 800$..so no good deal.

After installing the EVO, you can run them as separate volumes or fuse them together in a single logical "fusion partition" again. Up to you.

So speed wise, it's like this: 1TB Fusion < 850 EVO < SSUBX < SSPOLARIS
 
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Hi, I'm in search of the same thing.
I have an imac 27 "2017 with 1TB fusion drive and I want to buy an SSD pci to put it inside.
Although I have more information now, I still have doubts.
Are the SSDs that the macbook pro 2015 (SSUBX) are compatible with? beyond which it can lose speed. or if I have to buy an SSPOLARIS

Thank you
 
ricaguar wrote:
"I have an imac 27 "2017 with 1TB fusion drive and I want to buy an SSD pci to put it inside. Although I have more information now, I still have doubts."

My advice:
DON'T DO IT.

You'll void the warranty, and you could break something inside.

Instead, do this:
Buy an EXTERNAL USB3 SSD (a Samsung T5 would be a good choice), plug it in, and set it up to be your "external booter".

You'll get read/write speeds that will approach 85% of an internally-installed drive, and you won't void the warranty.

It's also VERY EASY to get a setup like that going...
 
Hum, I don't understand why you don't have read and write speeds that I have. I used black magic on my ssd and I'm getting 1850 write and 2300 read mb/s. :?

I have the same configuration of iMac and when I was running Sierra I had similar read/write speeds. However, since upgrading to High Sierra I am unable to test that 512 GB SSD. Get Info shows me as only being able to Read to this disk and I do not have privileges to change the permissions. Have you been able to use BlackMagic on your disk with High Sierra?
 
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I successfully replaced the hdd part of the 1TB fussion drive with a 250GB SSD.

The fussion drive was ok, but from past experiences, I knew my iMac would run faster with a sata ssd.

This was my first time opening the glued display. I bough 32GB of ram from owc and they sent me all the tools and the double sided tape needed to re assemble my 21.5" iMac. It took me around 4 hours to complete the ram and ssd upgrade.

I know the build to order ssd is much faster but I live in Mexico and here you can buy stock models and pay them in 24 months without any interests. BTO Macs don't have this 0% APR.
[doublepost=1502328187][/doublepost]For those who asked for benchmarks, I'm sorry I don't have screenshots. With the 1TB fussion drive I had read speeds varying from 90MB/s to 1200MB/s and write speeds from 80MB/s to 800MB/s.

Now I have constant read and write speeds of 450MB/s on my startup sata ssd and 800MB/s write and 1200 read speeds on my 28GB unfused ssd.
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hello, i just wandering if with the imac 21.5 2017 fusion drive i can upgrade the internal ssd with another one from a macbook pro 2014??
 
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