So, I'm thinking of upgrading my MBP (13' late 2011) with an internal SSD drive. I'm wondering if the increase in speed of read and write on the SSD internal drive, will increase peroformance and stability while reading data from other external HDD drives. I have a lot of data stored on external drives (iTunes, Photos, Audio sound libraries, ...) and wondering if I can expect significant improve on dealing with that external data on a daily basis. Thank you.

  • 1
    You can expect the machine to breathe more easily overall, windows open faster, everything a lot snappier. It won't necessarily affect the external drives as such, but it may feel like it does. BTW, I went for a 1TB SSD & mirrored my most-used sample libs to that to get the speed right up. iTunes & Pics etc I leave on other drives, same as you. For even more zippiness, you could work on projects from the SSD, & move to external once finished.
    – Tetsujin
    Commented Jun 24, 2015 at 14:59

2 Answers 2


Honestly, it is a waste not to have an SSD as an internal drive in a MacBook (or any computer in general), you will understand it once you have one. Of course, the speed of your internal drive has absolutely nothing to do with that of external ones. The latter is only governed by the respective bus speed they are connected to.

  • The bus on the internal one can also be a bottleneck. Commented Jun 24, 2015 at 22:08
  • Thank you guys for the info. The thing I'm wondering (but I admit my ignorance on the subject) is that if data from the external drives is temporarly copied to the internal disk for "operating access" (ex: will an mp3 file stored on the external drive and played on itunes on my mac be temporarly copied to my mac?) that maybe the faster internal drive would significantly improve my perceived performance. Am I simply assuming the wrong principles?
    – Mojo
    Commented Jun 26, 2015 at 13:40
  • Even if the fie from the external drive is copied to the internal one, the bottleneck is always the USB speed which in any case is much slower than the bus where the internal one is connected. Therefore, I would not expect any perceived increase in performance when working with files on the USB drive.
    – hobie
    Commented Jun 29, 2015 at 8:15

Using internal SSD will make your system faster overall, including access to peripherals.

With that said, you might or might not notice the access speed change to external HDD.

That would depend how busy the resources was/is. System will still use the RAM as means to communicate between the disks. Assuming you have no bottleneck there, next possible slow down would be your connection to the external HDD.

If it is USB2 you get what you get there is no way around that and you might not see improvement. But if it is Thunderbolt or USB3 then you will see a improvement.

Here are some numbers:

USB2 max speed is 60 MB/sec (480 Mb/sec). Typically you will get less than that so around 30-40 MB/sec. With Thuderbolt or USB3 you will get 10 times the speed of USB2. If your goal is to increase the access sped to external drives, the solution is obvious.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .