Why does my second ssd (on mac mini late 2012) is terribly slow ?

Question

Why does my second ssd (on mac mini late 2012) is terribly slow ?

OS X 10.10.1

Mac mini (Late 2012)

2,3 GHz Intel Core i7

8 Go 1600 MHz DDR3

Hello,

I put a second hd (240 Go Crucial CT240). But it doesn't run as nicely as i expected ;

I tried to install maverick on it, the process was incredibly slow and when i tried to use, it didn't work 😟

dual boot didn't work well with difficulties to reboot on the first hd (that is also an ssd this one work great ).

I now want to use it for data. Reading and writing on it is so slow.

I don't understand why ?

every informations on that topics is welcome 🙂

Mac mini, OS X Yosemite (10.10.1)

Posted on Dec 21, 2014 2:34 AM

Reply

Answer 1

Best reply

lllaass

Level 10

210,411 points

Dec 21, 2014 4:06 AM in response to Pierre antoine

Post the following information about the drive:

- Screen shot of Disk Utility with that SSD selected

- What system report says about the SSD, Click on Apple icon in upper left and select About This Mac. The System Report>SATA/SATA Express>the SSD in question

Reply

Answer 2

Dec 21, 2014 7:17 AM in response to lllaass

Here are what it show.

Reply

Answer 3

lllaass

Level 10

210,411 points

Dec 21, 2014 8:15 AM in response to Pierre antoine

The info you support show not problems

Go to Crucial's support site and make sure that you have the latest firmware for the SSD. If not update the firmware.

When boot from the good drive run Blackmagic Disk speed test on both disks and report the results. That app is free from the Mac App Store.

Some users have reported problems booting from an SSD installed in the upper bay, the bay normally empty for the the non-server Mini, for the 2012 Mini.

Was the upper bay empty on yours? No one had been able to determine the cause. Maybe because of the third-party cable or the drive controller.

Reply

Answer 4

Dec 21, 2014 11:02 AM in response to lllaass

Thank you, for your informations.

I now try to update the firmware, i will report informations once it's done.

Reply

Answer 5

skeewiff

Level 1

0 points

Jun 25, 2015 5:09 AM in response to Pierre antoine

Did you manage to get this to work?

I too have just installed a second SSD in a Mac Mini 2012 (Non Server). The SSD in question a crucial MX100 500Gb is also connected to the "Upper Connector" and also does not work properly. It is slow and inconsistent. Blackmagic Disk Speed Test reveals that although starting with decent write speeds in the late 480s, it suddenly drops to around 50.

The Samsung EVO 850 works beautifully in the lower connector. No issues.

Is this likely to be a dual SSD thing. Or dual anything thing? Wouldnt want to go through that procedure all over again to find that the original HDD doesnt work in the upper tray either.

Reply

Answer 6

skeewiff

Level 1

0 points

Jun 26, 2015 12:46 AM in response to Pierre antoine

Great Success! I can confirm that a Firmware update to the Crucial MX100 512Gb worked. 🙂

Updating it wasnt the easiest task - But I found this guide on making a bootable flash drive over at MacRumors, which worked great. It took the firmware from MU01, to MU02 which seems to have fixed the issue completely.I now have a dual SSD Mac mini.

Reply