Ultra Fit USB 3.0: Excessive Heat

@roadranger wrote:

I have a 32GB that seems to not overheat like my 128GB does. In any case the solution is simple - just use a USB2.0 port when writing large amounts data to it.

In that case, it defeats the purpose of buying a USB 3.0 flashdisk.

@chin wrote:

In that case, it defeats the purpose of buying a USB 3.0 flashdisk.

In my case I keep it plugged into a USB2.0 only device for music playback. While it would be nice to be able to wrte to it on a USB3.0 port I rarely do that now that I have it loaded up :slight_smile: .

Hi, I removed the plastik and metal casing and inserted it into a USB port but the Ultra fit wont work and its not recognized. I was hoping the heat can get away much better like that. Is there some ground not touching when naked without its metal housing? The pins on the USB seem to connect fine when inserted.

You understand the metal is what helps dissipate the heat, right? Removing it does more harm than good.

Mine Utra Fit 128Gb died (permanently gone to the read only state) after 11 month of work, very hot work. R.I.P.

(I posted a ‘solution’ earlier, but the links to the suggested cable, are now not supplying a suitable cable - fit is too loose )

Here is my solution -

Purchase an extension cable (Male and Female ends) that will help dissipate the heat. The female end has to have no rubber covering so that it is metal to metal and the metal is exposed to the air.

Also I (very much) like the female end to provide a VERY snug fit for the SanDisk thumb drive

This helps keep the heat manageable, and prevents any damage to the usb soclet on your laptop(etc)

I recently browsed eBay looking for a current sale that might match my requirements.

I just received one today and it is perfect.

Here is the link -


I just ordered another 6, so be quick (He is only showing 4 left)


negusp, that was not the question and I think no, the metal will not conduct the heat well.

The extension cable is not a solution. Why would I buy a miniature Usb device and attach a cord and an adapter, thats ridiculous. 

Is anyone able to make the naked board work in an USB slot?

The metal will conduct heat far better than using a naked board.

What do you think heatsinks do? They dissipate heat from the main board by spreading heat over a larger surface area. The metal is crucial in this.

That is exactly what the extension intends to do, but more effectively. A naked board is not an effective solution.

sure, I must have missed the copper and heat conducting paste when opening. 

Anyone know why it doesn’t run board only?

Does it work when you reassemble it? You might have broken it with your clumsy handling :stuck_out_tongue:

“Anyone know why it doesn’t run board only?”

It wasn’t designed to run that way?

I am seeing a mirror image of mine. Hats of to you and you have proved their design is wrong. Very happy to see you post here

"Anyone know why it doesn’t run board only? " - well my iphone doesn’t run screen only. Any guesses why? :slight_smile:

Don’t worry about heat. It shouldn’t get too hot to operate. If it does, the manufacturer failed you so you can get it replaced. Just be sure to be reasonable and keep it fairly well ventilated.

Don’t worry about heat. It shouldn’t get too hot to operate.

If it does, the manufacturer failed you so you can get it replaced.

Just be sure to be reasonable and keep it fairly well ventilated.

I believe the concern is the laptop USB port it is connected to as well as the data in it.

Replacement only cover the USB Flash Drive, not the data neither the laptop USB port (if it is damaged due to overheat from the USB Flash Drive).

While other manufacturer also does not provide any warranty to cover the data (in case of loss) neither the USB port of any laptop, however, the USB Flash Drive from other manufacturer does not operate under that high temperature (at least the temperature of the touchable surface of the USB Flash Drive).

The workaround is to use extension cable, but other’s opinion is also valid as like why should I buy a tiny USB Flash Drive but end up with attaching an extra USB cable? It against the tiny design!


So, its been a while, and I’d like to comment back on this USB. I’ve had it for over a year, run several Linux distros on it, and currently use it to store ROMs/Kernels/Flashables for my Nexus and Galaxy phones- in short, it works great as small expandable storage.

As a USB 2.0 device, that is. I’m highly disappointed in the heat department when used as a 3.0 device, but for such a small USB and form factor I’m not surprised. When I need to get stuff done, 3.0 does the job but man, the heat is  insane.

Even so, USB 2.0 speeds and heat development are actually very decent. Read is around 70 MB/s while Write is around 50 MB/s. Nothing blazing but plenty fast for any self-respecting Linux distro out there. Heat is no problem when connected to a 2.0 port- for a few months I was running Steam games daily from it.

So overall, for the $11 I spent for this little guy I’m satisfied. I think Sandisk ought to inform customers, however, as there are many people in this thread who haven’t had nearly as rosy an experience as I.

yes i also having this problem i bought just on 10 feb 2017 can this be exchange or repair but i dont have bill but i have box

Well, I feel I’ve got to add my two-penn’orth to this saga.

I use a pair of the 64GB Ultra Fits as external storage on an ancient Dell Inspiron laptop…an original 1100, from 2002/3.

I run ‘Puppy’ Linux on this (which as y’all know, runs entirely in RAM; Puppy ‘lives’ on a 64GB KingSpec IDE/PATA SSD). The drives are formatted as ext3, and are used purely for data storage. Like many others on here, I too have found that they run pretty hot…but my observation, over a period of time, is that they run hot up to a point (but then no hotter.)

I’m guessing that the R&D guys have determined that the heat levels are acceptable…but I have to agree with xcalibur, back in post#35; I too think it’s a basic engineering problem. You’re cramming 128 GB of NAND flash memeory into something that small, along with all the necessary controllers, etc, and then running at 130 GB/s read speeds, something’s got to give…and it comes out as heat.

I’ve never had the problem exhibited by joeydee, in those rather alarming photos he posted. The plastic ‘end-cap’ on my own Ultra Fits does indeed get warm…but again, only up to a point. I’ve examined the plastic surround of my own USB ports, and there’s no actual sign of any damage. Mind you, this machine runs a full desktop Northwood Pentium 4…and the older guys amongst us will remember how insanely hot those things used to run. It’s quite possible Dell took that into account when designingthe 1100s, and accordingly used suitable thermoplastic in the construction…

I run a 3rd 64GB Ultra Fit plugged into the back of our router, as a small NAS drive. It works fine, and in fact gets nowhere near as hot as the others do plugged into the lappie. Overall, I’m quite happy with my Ultra Fits; I’ve been using SanDisk flash drives for years, and with the exception of the Cruzer Blades, have never had any complaints.

(It’s no joke when you take a ‘dodgy’ Blade apart, and find out there’s only the stub of a circuit board inside it, with the USB contacts…and NOTHING ELSE. No NAND flash chip, no controller circuitry; weird…!)

I’ll reserve judgement on that one…

Mike. :wink:

I just bought 2 SanDisk - Ultra Fit 32GB USB 3.0 Flash Drives from Walmart and after a few mins I noticed the metal case on side of my MacBook pro where one unit was plugged in became warm to the touch and when I removed the drive the metal shell was so hot it was nearly untouchable. I noticed this on an Android tablet and that it noticed it cut my battery time by 40% when just setting idle. I’ve got an old Cruzer Fit that does not get hot like these things do!

Thinking it may be due to some constant data access I plugged it into my Iphone USB power adaptor and it becaame very hot as well,  so it can’t be due to data access. 

As hot as this unit gets seems not normal, and with all the reports of hot drives  going on three years now on this thread alone, I’m wondering if it could be a counterfit issue?