I'm mainly talking about the speed here. I have a 120GB SSD installed in my laptop and I'm loving it. However, 120GB is really size prohibitive. My other slot is filled with a 1TB HDD so it's not an option to get an extra SSD in that slot and paying for a larger SSD just to replace my current one is not worth it.

So I'm considering some other interesting alternatives. I could get an external SSD, but honestly it seems like a decently sized one costs so much more than a simple flash drive of same capacity. Now, I don't really know the difference in their construction, but a flash drive also has no moving parts. Is it slower than a SSD? Why would anyone want an external SSD otherwise?

In any case, I'm wondering if I would have any performance benefits from buying a USB3.0 flash drive and using it as an extra disk over just using my HDD. If not, would an external USB3.0 SSD make a difference?

  • Try looking into swapping out your ODD with an SSD cage. These days ODD are barely used, you can just place it in an enclosure if you need it. Or try find out if your laptop has place for a 2nd HDD, some do but it's never disclosed and you can't know until you open the HDD area.
    – JasonXA
    Apr 18, 2015 at 11:29
  • @emm980 As it happens, my laptop has the only working ODD in the family :D Can't get rid of it. The laptop did originally have 2 HDDs but I swapped one out for an SSD.
    – Darwin
    Apr 18, 2015 at 11:31
  • Not getting rid of it, but "externalize" it.
    – JasonXA
    Apr 18, 2015 at 11:32

2 Answers 2


The flash used in flash drives has always been slower than that of SSD's due to cost, compounded by the fact that the USB 3.0 interface is limited to 5 gbit/s. SATA III on the other hand is limited to 6 gbit/s, and even SATA is being phased out for the faster NVMe interface. It could work, in theory, but I would always be cautious as to using something that could be removed very easily by accident as a permanent drive. Premature removal could lead to data loss/corruption, etc.


A flash drive is a LOT slower then an SSD, and it's not because if the Interface. A typical SSD has read and write speeds well in excess of 300megabytes/second. A flash disk would typically have 1/10th of that.

SSDs also have much higher endurance ratings then flash. While using flash for occasionally accessed documents use is OK it's not a replacement for an SSD.

(Flash generally use mlc chips while SSDs use SLC. SSDs have more complex controllers and access to the chips which can greatly improved performance)

An external SSD will make a difference, and will perform somewhere between an internal hdd and SSD if used with USB3.

Of course, 120 gigs of SSD is only worth $70 or so, so it might work out better to replace your 120gig one with something bigger - that will give you more performance, portability and reliability.

You must log in to answer this question.

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