Dual internal hard drives in Mac mini?

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Dual internal hard drives in Mac mini?

Hello all -

I have a mid 2011 Mac mini, 2.7 MHz, i7, 8 GB Ram with the 7200 RPM Western Digital 750 GB factory upgrade drive. (Macmini 5,2) I'm planning to upgrade to a Solid State Drive (SSD). My choice is to either install the new SSD as a second internal HD in the mini, or to pull the old conventional drive and retire it to an external enclosure, leaving the new SSD as the sole internal HD in my mini.

I'm familiar with the fact that my model has space for a second internal 2 1/2 HD, and also has a second SATA connector on the mother board. I know that several places (such as iFixit and OWC) offer kits to add a second internal to my model. I've seen statements in several palces that benchmark testing has established that which bay a drive is installed in makes no difference as to its performance, apparently either drive will work equally well in either bay position.

So now I'm trying to decide whether to remove the mechanical WD drive to an extenal enclosure or leave it in. My question is, will having 2 internal drives both operational degrade performance? If so, any idea how much? BTW my Mac mini model is SATA 3 6GB. Are there any other factors to consider in making my decision?

Thanks a lot for your comments! - Randy

Mac mini, Mac OS X (10.7.5), (mid 2011); 2.7GHz i7; 8GB RAM

Posted on Nov 22, 2012 12:38 AM

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Answer 1

Best reply

woodmeister50

Level 6

19,771 points

Nov 22, 2012 2:16 AM in response to Randy Knowles

Randy Knowles wrote:

...... My question is, will having 2 internal drives both operational degrade performance?

There will be no performance degradation at all. The SSD will much

improve OS performance and can speed up any disk intensive apps

if you put the data files on it while working on them. The HDD will

still be accessed at the same speed it was before.

Also, some activities could be sped up if an app uses some temporary

caching on the boot disk. This is because it would be pushing data from

one disk to another, instead of back and forth off the same disk.

The only factor to consider in your decision is your ability to handle

working with deilicate components. If you have seen the videos on

OWC for replacing/adding a drive in the Mini, it is not for the unskilled.

Not sure how old your Mini is, but if it is still under warranty, doing the

SSD install will void it. So, if you break something, you will pay full

price for any repair.

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Answer 2

RRFS

Level 5

4,522 points

Nov 22, 2012 10:10 AM in response to Randy Knowles

The new Disk Utility may have issues.

http://blog.macsales.com/15619-special-note-for-adding-an-ssd-to-a-2012-mac-mini ?replytocom=61641

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Answer 3

Nov 22, 2012 12:37 PM in response to RRFS

This would be true if the OP had stated he had a 2012 mini. His is a 2011.

It does raise a question for the disk utility behavior in 10.8.3. Bound to bite a few unsuspecting people who do not want a Fusion fiasco.

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Answer 4

Nov 22, 2012 12:52 PM in response to Randy Knowles

The two things you need to bring to the SSD upgrade party is plenty of patience, and the OWC (macsales) Mac mini SSD drive kit. Oh, and a 9.5 mm, fast SSD compatible with Mountain Lion and with current firmware. The drive should be large enough that in operation, it is not more than 50% capacity, or slower drive algorithms in the SSD controller may slow the device down. That is the caution with my Vertex 4.

I installed my SSD as a primary boot/application/user drive, and left the original 500GB drive in place. To uncomplicate having two drives mounted with OS X 10.8.2, I created an /etc/fstab file on the SSD that blocked mounting the original HDD on boot. Using Disk Utility, I can still mount/unmount that HDD any time after boot.

There is no reason why you can't leave the original HDD inside the mini. On the otherhand, with a compatible external USB3 enclosure, it might find even more utility as a shared or backup device. I think once you tear the mini apart to do the SSD install, you may not want to do this again to remove the HDD.

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Answer 5

RRFS

Level 5

4,522 points

Nov 22, 2012 3:38 PM in response to VikingOSX

I do believe that the 10.8.2 recent update (unknown build not 12C60) has been pulled as there are lots of posting indicating the inablilty to update to 10.8.2 from 10.8.1.. I know we don't speculate here but I'm guessing that Apple didn't want to make it possible for users to create their own Fusion Drives seeing as they can charge a premium for their proprietary drives. 👿

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Answer 6

Nov 22, 2012 8:41 PM in response to woodmeister50

Thanks woodmeister -

So you are saying that the performance of the SSD will be the same, whether it's all by itself or in tandem with the WD HDD. That's exactly what I wanted to know. I guess it boils down to how much I might want to use the old HDD. If I put it into a Firewire enclosure it's going to be a lot slower. So if I want to use it very often then I should leave it as an internal.

As to doing the install, I feel pretty confident as I have done this before on older Mac minis, which were even more complicated still. However, I do have the 3 year extended Apple Care Plan, which has 1 month less than 2 years to go. Will I loose being able to call in on that, and/or get repair of any unleated problems in the future? (For example, with my last Mini the Firewire port went bad before the end of the 3 year period and Apple fixed that under my extended Plan.) I understand that if I make a mistake and break anything in doing the SSD install I would have to pay for the repair.

Thanks again for your comments. - Randy

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Answer 7

Nov 22, 2012 9:09 PM in response to VikingOSX

Thanks for your comments Viking -

As to the 50% capacity matter, I am good there. I was planning on getting a 240 GB. I currently occupy 75 GB on the Mac side and 16 GB on the Boot Camp side, so I will be well under 50% on the SSD. Is the 50% parameter applicable to all bands of SSD's? I was thinking of getting the OWC brand drive.

I am also planning to have the SSD be my primary boot drive. I currently have 2 other external drives (with a total of 9 partitions). These are, for the moment, Firewire 800. Hopefully after Christmas these will be Thunderbolt (with the Seagate GoFlex adapter). You mention having 2 drives mounted under 10.8.2 being "complicated". Since I am still on 10.7.5, I'm not familiar with this. Is there some problem having more than 1 drive or partition mounted with 10.8? How about with 10.7, I've not seen anything obvious so far with Lion.

Since I'm on a mid 2011 mini, I don't have USB3, only the slow USB2. That's why I am taking my existing externals (Seagates) to Thunderbolt. At present I don't know any way to make my existing Western Digital an external drive other than as USB2 or Firewire 800. Am I missing something here?

Thanks again for your response. - Randy

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Answer 8

Nov 23, 2012 12:38 PM in response to Randy Knowles

Is the 50% parameter applicable to all bands of SSD's?

This was a cautionary technical note for the OCZ Technologies Vertex 4. Read the details that OWC states for their drives, and the technical support section, for currency of firmware updates. I believe the 50% factor above may vary by manufacturer, and how they implement their controller firmware. Apple blocks TRIM support in non-Apple sourced SSD drives. Manufacturers get around this by implementing it in their controller firmware.

You mention having 2 drives mounted under 10.8.2 being "complicated". Since I am still on 10.7.5, I'm not familiar with this. Is there some problem having more than 1 drive or partition mounted with 10.8?

There is no functional or thermal problem with multiple drives spinning simultaneously. I had some issues with the App Store perceiving two different Apple ID when only one existed. This resulted in blocked app updates until I got it sorted. Your experience may be completely different.

OS X running on the SSD will attempt to find things it deems missing on the OS X installation on the HDD. It may have been seeing two installation receipts, and two Keychains and got confused. The SSD was a current clean 10.8.2 install. The HDD had one OS X update on it to 10.8.2. Probably will never know precisely what confused it. Decided to leave the HDD unmounted at boot, but as yet, undecided about its future use.

At present I don't know any way to make my existing Western Digital an external drive other than as USB2 or Firewire 800. Am I missing something here?

Those are the only two financially practical solutions. OWC resells a portable, external Thunderbolt drive consolidation solution by drobo. It is expensive. And of course, there is a Network Attached Storage (NAS) solution, by example, Synology DiskStation. There is one of these down the hall.

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Answer 9

Nov 23, 2012 11:43 PM in response to VikingOSX

Viking - Thanks so much for your further response.

I re-read the OWC info for their drive and verified I had not seen any mention of the 50% issue. They have a very limited specs section whcih talks about speed and reliability factors (including 7% ovderprovisioning, write exhaustion avoidance, wear leveling, etc.). That being said I have learned over the years that sometimes the most important thing is what is not said, rather than what is explicitly stated. So I guess it boils down to how much do I trust OWC to be forthcoming. My impression is that they are pretty straight shooters. Maybe someone here will tell me otherwise. I did check the drive at PassMark last night and was astonished to find it listed only as number 264 (score 1311), not even in the first 100. I am willing to sacrifice speed for reliability to a point, but now I'm wondering ..... I know that OCZ drives are number one and two on the list, but I've seen some coments about reliability for them. I do find the OWC 5-year warranty and unlimited lifetime support attractive.

OWC does list a firmware update for the drive, but the directions for ascertaining if it's necessary involve looking at the system report with the drive installed, of course. LOL

As to the 2 drives simultaneously question, I made two observations from your comments, it I followed them correctly. 1st: Both your SSD and your HDD are boot volumes; 2nd: You are on Mountain Lion where software update has been moved to the App Store.

Initially of course I would leave the HDD as it is currently (as a boot drive). At least until I could fomat the SSD, add the BootCamp partition, and clone everything over. Currently I am contemplating then reallocating the HDD to hold two volumes from old FW 400 externals - these would not be bootable. Hopefully that would avoid the problem you describe, if I can get to that point before difficulties arise.

The drobo stuff is interesting but too expensive/overkill for my current uses. Between keeping my 7,200 rpm WD HDD internal and upgrading my Seagate external with the Thunderbolt GoFlex Adapter, I would be able to eliminate all my old FW 400 and FW 800 drives. Based on tech specs alone (not real world, I know) I would expect the Seagate external to be even faster than the WD HDD internal.

Your comments have been very illuminating and helpful. Thanks again for your time and the benefit of your experiece!! - Randy

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