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Help deciding 512gb or 1tb SSD for new iMac 2017

So I've just some tests that I think are pretty conclusive (to me).

Connecting the Samsung T1 (USB3) to the 2016 4K iMac with 2TB fusion drive (128GB SSD "cache"). Copying a folder of around 6GB (12 files).

Fusion to fusion direct copy. Around 100 MB/sec
Fusion to T1. Same - approx 100 MB/sec
T1 to T1: Around 250 MB/sec. (Combined read/write to same drive yet still >200MB/sec)

I think it is clear that my fusion system is held up by the mechanical spinner. If the internal was a pure SSD, I suspect internal to T3 would be much higher than 200 MB/sec.

So: if on a tight budget I think definitely avoid the Fusion if you are going to be working on large (>1GB) files frequently and go for the smallest (256GB) option for OS and apps.Then put everything else on an external T3 USB-C. File performance will be very fast, plus it is flexible (take your data with you if you need to) and expandable.

Of course, if money is no option then certainly go for the 1-2 TB internal PCIe SSD.
 
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Shivetya said:
If you are trying to save a few hundred dollars on a two thousand dollar purchase then maybe you should reevaluate how much you are spending in the first place.
Click to expand...
So just because the computer is expensive, asking whether an upgrade adding 20 % to the price is worth it since he can get more for less by going a different route is a sign that he should reevaluate the entire purchase? That logic seems a bit flawed...
 
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Anybody know what brand of SSD's are installed in the new iMacs? Are the read/write speeds similar between 512gb, 1tb, and 2tb ssd's.
 
Spectrum wrote above:
"So I've just some tests that I think are pretty conclusive (to me)."

How about using BlackMagic Disk Speed Test to post the results of reads/writes to the T1 ?

I'll bet they're a lot higher than what you posted above.

You should get reads around 430mbps. That's what I get with a Crucial SSD in a USB/SATA dock.
 
Spectrum said:
I'm actually considering getting the mid-model 5K iMac and then upgrading to the i7 7700K CPU. The benefit is that you can spec a 256GB internal SSD, bringing the upfront cost even lower. My idea is then to keep the internal just for System and user folders (small), then to put my entire Dropbox folder on a fast external USB3.1 (or TB3) drive that I can upgrade as an when I need to.

Does anyone foresee a problem with this strategy?
Click to expand...

The only comment I would make is ensuring the GPU meets your needs as well. There is some difference between the 570 and 580 other than the additional 4g VRAM. :apple:
[doublepost=1497456357][/doublepost]
niteflyr said:
Anybody know what brand of SSD's are installed in the new iMacs? Are the read/write speeds similar between 512gb, 1tb, and 2tb ssd's.
Click to expand...

Can't find any benchmarks yet. I'd wager they are VERY fast. :apple:
 
I went with a 1TB in my 2015 iMac 5K refurb as it was the only option available (along with 32GB of RAM, unfortunately). I had a 512GB drive in my 2014 iMac 5K and I started to run out of space (I do have a 16TB Drobo 5D but I save a lot of temporary media files to my local drive and I had a large Boot Camp partition for games) so I was inclined towards the 1TB anyway, but if I could have found a 512TB/16GB refurb, I probably would have bought it for the savings.
 
Personally I prefer to have more internal space it it's so hard to justify Apples pricing, even if run at phenomenal speeds
 
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Glideslope said:
Can't find any benchmarks yet. I'd wager they are VERY fast. :apple:
Click to expand...

512 GB SSD in the mid range 21.5" 2017 iMac.
iMacDiskSpeedTest.png
 
Glideslope said:
Impressive. Who is the manufacturer? :apple:
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According to what I could find it appears to be a Samsung SSD, SM1024G. I was actually expecting the SSD, in the 2017 iMac, be around the same speed as the SSD used in the 2016 MacBook Pro which is about 3GB/s. Maybe the SSD in the 27" is different from the one used in the 21.5".
 
Taz Mangus said:
According to what I could find it appears to be a Samsung SSD, SM1024G. I was actually expecting the SSD be around the same speed as the SSD used in the 2016 MacBook Pro which is about 3GB/s.
Click to expand...

Thanks. Most likely correct. I was assuming 15% tops. 30% is big. Looks like a lot of new engineering in these new iMacs. It's nice to feel good about a new Apple Hardware release for a something other than a phone. ;)
 
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Glideslope said:
Thanks. Most likely correct. I was assuming 15% tops. 30% is big. Looks like a lot of new engineering in these new iMacs. It's nice to feel good about a new Apple Hardware release for a something other than a phone. ;)
Click to expand...

Maybe I was not clear about something. The SSD in my 2015 27" iMac is the SM1024G by Samsung. I don't know who is supplying the SSD for the 2017 iMac.
 
The internal SSD on the 27" should be ~2000MB/s Write and 3000MB/s Read. The additional 500G will cost $400 more. You can't even come close to that performance in an external drive without spending considerably more money. If you ever think you can use this (Pro Audio, or Video editing I would assume) - then spend the extra $$. FWIW - I did :). If all you need is bulk storage - 1TB SSD in USB3 is ~$350 and will do ~350MB/s.
 
Fishrrman said:
Spectrum wrote above:
"So I've just some tests that I think are pretty conclusive (to me)."

How about using BlackMagic Disk Speed Test to post the results of reads/writes to the T1 ?

I'll bet they're a lot higher than what you posted above.

You should get reads around 430mbps. That's what I get with a Crucial SSD in a USB/SATA dock.
Click to expand...
Sure. Using the 1GB test file size on Black Magic is:
Internal 2TB fusion: 600-650 MB/sec write, and anything from 600-1700 MB/sec read
External USB3 512GB Samsung T1: 370 MB/sec write, 425 MB/sec read.

It is notable that the performance of the Samsung is identical every time. The fusion varies a huge amount.

NOTE: These speeds are for the 2016 4K iMac.
 
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The ssd should be a custom samsung 960, the same of the 2016 macbook pro since they didn't release any new ssd. So if you want to see write/read speed just go search for them.
 
btrach144 said:
I'd hold out for the Samsung T5.

You can also consider the Sandisk 900 extreme. Over 800 MB/s (if you use USB-C 3.1)
Click to expand...
ooh thank you for the heads up. Didn't know a thing about the potential T5 until you mentioned it here. Definitely will keep an eye out for that.

I looked at the sandisk 900 extreme, its definitely a contender. Don't need it right now, so will wait and see what else comes out.
[doublepost=1498034112][/doublepost]Thanks for everyone's input. I opted for 512gb in the end as I didn't need a bigger internal working drive for now, so figured best to save the extra money and see what external solutions there are when i eventually need it.
 
Spectrum said:
I'm actually considering getting the mid-model 5K iMac and then upgrading to the i7 7700K CPU. The benefit is that you can spec a 256GB internal SSD, bringing the upfront cost even lower. My idea is then to keep the internal just for System and user folders (small), then to put my entire Dropbox folder on a fast external USB3.1 (or TB3) drive that I can upgrade as an when I need to.

Does anyone foresee a problem with this strategy?
Click to expand...
Yes. 256 is too small for a high end machine with no room to grow. You'll regret it.
 
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Sirmausalot said:
Yes. 256 is too small for a high end machine with no room to grow. You'll regret it.
Click to expand...
Yup. I went 1 TB with my iMac. I think 512 GB is the sweet spot for most (noting that the current iMacs have fast external IO options), but it's cramped for me.

OTOH, I went 256 GB for my MacBook with 16 GB RAM. I've been using 120 GB up until now and it's been OK for me.
 
1tb. My understanding is that once it reaches 50 percent of your drive, computer starts to slow down.
 
pat500000 said:
1tb. My understanding is that once it reaches 50 percent of your drive, computer starts to slow down.
Click to expand...
There shouldn't be this problem with internal ssd. Only with external on usb 3.0, where you can't activate TRIM, once they reach 80%.
 
Spectrum said:
So I've just some tests that I think are pretty conclusive (to me).

Connecting the Samsung T1 (USB3) to the 2016 4K iMac with 2TB fusion drive (128GB SSD "cache"). Copying a folder of around 6GB (12 files).

Fusion to fusion direct copy. Around 100 MB/sec
Fusion to T1. Same - approx 100 MB/sec
T1 to T1: Around 250 MB/sec. (Combined read/write to same drive yet still >200MB/sec)

I think it is clear that my fusion system is held up by the mechanical spinner. If the internal was a pure SSD, I suspect internal to T3 would be much higher than 200 MB/sec.

So: if on a tight budget I think definitely avoid the Fusion if you are going to be working on large (>1GB) files frequently and go for the smallest (256GB) option for OS and apps.Then put everything else on an external T3 USB-C. File performance will be very fast, plus it is flexible (take your data with you if you need to) and expandable.

Of course, if money is no option then certainly go for the 1-2 TB internal PCIe SSD.
Click to expand...
I did some testing for you with my MacBook. My 2017 MacBook has an SSD but it's only half as fast as the 2017 iMac's. However with my external USB 3 SSD I get 344 MB/s read and 312 MB/s write... On a lowly MacBook.

The drive IIRC is a Samsung 850 EVO 512 GB, in an OWC Mercury Pro Elite USB 3 (and FireWire 800) enclosure.

This is why I went with SSD for my new iMac. No platter drive or Fusion drive for me in 2017.
 
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EugW said:
I did some testing for you with my MacBook. My 2017 MacBook has an SSD but it's only half as fast as the 2017 iMac's. However with my external USB 3 SSD I get 344 MB/s read and 312 MB/s write... On a lowly MacBook.

The drive IIRC is a Samsung 850 EVO 512 GB, in an OWC Mercury Pro Elite USB 3 (and FireWire 800) enclosure.

This is why I went with SSD for my new iMac. No platter drive or Fusion drive for me in 2017.
Click to expand...
With sandisk 900 or samsung t5 (not released yet) on thunderbolt port you will get 800 read/write
 
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