Ultra Fit USB 3.0: Excessive Heat

I don’t believe Windows will transfer any single files over 4GB.

True, but the solution for removable drives is not NTFS, it’s exFAT.  No journaling, less overhead, less heat. And the format the drive comes with.  Did you try transferring your 5GB file before formating the drive?

As for booting a removable drive check out the Easy2Boot app.  http://www.easy2boot.com/

Hi all,

I registerd here just to express that I am completely disappointed by this flash drive.

I was trying to copy a 9GB file to the flash drive - and it kept disconnecting because of overheat after ~7GB of transfer.

After each failure I was waiting for it to cool down. from the 4th try I managed to copy that file, but after I disconnected the drive - it is not detected anymore in OS. So it died completely (I tried several other PCs as well).

Why to manufacture a product which fails its primary purpose - file transfer??

@artci: I completely agree with you. I have been a fan of Sandisk for CF, SD and now USB stick. Sandisk never let me down until this Ultra Fit, which completely changed my impression about Sandisk.

My opinion is, this is a defect product. And after many complaints in this “Sandisk forum”, seems like we are talking to the wall.

Regardless the theory that cramming a high speed chip into a tiny form factor will definitely produce heat, but this fails the main purpose (copying files). If Sandisk cannot produce a decent product in this form factor, they shouldn’t at the first place.

I own both. The Cruzer Fit is still fine, while Ultra Fit is not.

Maybe a campaign against Ultra Fit will draw Sandisk’s attention?

Pretty disgusted with the way you have all been treated. I too had an Ultra Fit - albeit 128gb with the same problems./ Today I exchanged it to a comparable one made by Strontium and it is running fine. 

When will companies realise that the way they deal with customers if things don’t go according to plan (i.e. defective goods) is enough to lose their custom.

I for one will not be buying san disk anymore. 

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My 64GB FIT has run very hot from day 1 when copying files or formating. It is so hot I can’t touch the metal part for more than 2 sec while in use and I have to wait a few min to cool down after pulling it out. While at idle it is just slightly warm. I only use it in a 3.0 port on my 1 year old MSI gaming laptop. It obviously is not a hardware issue since there are so many reported heat problems even in new computers. A design flaw in the Fit has to be the problem . I’m also getting terrible write speeds of only 23MB/s when it should be around 100 MB/s. My read speeds are better than spec at 145MB/s but that doesn’t make up for the write speed. I will not get any more Ultra Fits at any price, I will try the Extreme 64GB next.

To continue my previous post…

(I wrote this already, but my post got lost, so I’m typing it in Notepad first… yeah, that’s handy).

I contacted SanDisk support about my issue. They assured that the drives were tested for safety and compliance, but they agreed to replace them by another equivalent model. The RMA process took  ~2 weeks and in the end I got my UltraFit drives replaced by 2x full size “SanDisk Ultra USB3 64GB”. They seem to work fine without issues - there is no speed drop and the drive remains barely warm during large file transfers (~10GB).

Despite I was not happy with the product (UltraFit), I admit that SanDisk support was helpful and resolved my issue by replacing the drives with another equivalent model.

Thank you!

PS: certain people with a “Guru” badge here claim that the issues are caused by filesystems or some other mythological reasons. That’s wrong. A storage device should not care what filesystem or OS is used as it should be designed to work correctly under any load providing the ambient environment is within its limits. Please do not confuse people with your silly myths.

@artci: “replace them by another equivalent model”, did you mean they were not replaced with Ultra Fit? Any chance to share what is the repalcement model which works well?

“there is no speed drop”… would you mind to share what is the average write and read speed you can achieve with the replacement model?

Agree with your comments re. filesystems.

I guess enough people have replied… but here’s my reply from experience: Yes the ultra fit does get too hot, but its ok - there’s no problem other than that. Its been working fine for me for the past 1 year with moderate activity. Just some thermal dissipation folks, bear it for the small size :):smileyvery-happy:

@electronicsguy: have you had a chance to see the case of one of the poster here? http://imgur.com/a/sEtdj

I did a small temperature measurement test.

With the ambient temperature around 30’C, the Ultra Fit temperature is as high as 68’C during files were copied into it and the copy process looks like intermittent while the transfer speed dropped to around 18 MB/s (while usually it could reach up to 45 MB/s or higher).

When I put a fan continuously blowing directly to the Ultra Fit (at approx. 8 cm distance), the temperature dropped to 46’C.

I did a small temperature measurement test.

With the ambient temperature around 30’C, the Ultra Fit temperature is as high as 68’C during files were copied into it and the copy process looks like “intermittent” while the transfer speed dropped to around 18 MB/s (while usually it could reach up to 45 MB/s or higher).

When I put a fan continuously blowing directly to the Ultra Fit (at approx. 8 cm distance), the temperature dropped to 46’C.

The temperature was measured with Infrared Thermometer which has 1.5’C accuracy tolerance.

The Ultra Fit specification as stated in Sandisk portal is:

https://www.sandisk.com/home/usb-flash/ultra-fit-usb

Available capacity: 16GB, 32GB, 64GB and 128 GB
Performance/Speed: Up to 130MB/s read; write speeds lower
Dimensions: 19.1 x 15.9 x 8.8 mm; 0.75 x 0.63 x 0.35 in (LxWxH) – without cap
Operating Temperature: 0 C to 45 C
Storage Temperature: -10 C to 70 C
Compatibility: USB 3.0 (backward compatible with USB 2.0)

Does this mean my Ultra Fit temperature during file transfer (WRITE) at 68’C has way surpassed the specified max Operating Temperature (which is 45’C)? Would anyone kind enough to shed-the-light?

@Chin

“did you mean they were not replaced with Ultra Fit? Any chance to share what is the repalcement model which works well?” - SanDisk Ultra USB3 64GB, I did not chose the model, but specifically stated that I do not want a microdrive anymore.

“would you mind to share what is the average write and read speed you can achieve with the replacement model?” - a quick test shown ~100MB/s sequential read and ~50MB/s sequential write. While not great, but it is fine - also the flash drive remains barely warm with a load that killed the UltraFit (copying to flash drive a VHDX disk image of size ~10GB).

I am happy now with the “quality for price” I got with these new drives.

 @chin … well one person doesn’t mean anything. As I’ve said from experience…using it for a year, moderate use. no problems.

@chin how did you measure the ultrafit temperature?

@electronicsguy: As mentioned earlier, the temperature was measured with Infrared Thermometer which has 1.5’C accuracy tolerance.

“well one person doesn’t mean anything.” This statement also includes yourself Electronicsguy. Obviously there are lots of people that have Ultra Fits that are not functioning properly. I don’t have a digital thermometer to measure mine but as I stated when writing or formatting I can only touch it for 2 sec so it must be at least around 70 deg. Also the write speeds fall below 23MB/s so this is not functioning properly and is defective. These all should be recalled if they are running above 45c. No wonder Sandisk drives are some of the cheapest drives on the market. The only flash cards & drives that I have ever had fail/problems with are Sandisk. Anything Lexar I have ever got have been flawless and I will to continue buy Lexar instead of Sandisk.

yes ofcourse it does. but if there was a design fault, it would have been recalled. people are only complaining because its get much hotter than bigger (normal sized) usb drives. speeds fall and vary even with normal usb drives. that’s not a fault by itself.

Yes because manufactures are ALWAYS forthcoming when it comes to product recalls no matter how much money it cost them :smileyvery-happy:. How about VW diesel cars of today? If manufactures can get away by ignoring the problem and hope a government agency doesn’t find them out they will.

Yes and the only people who write on forums are ones with a complaint. the others don’t write. Is there any specific problem you have with the ultrafit other than heat or varying speeds?

@electronicsguy: I believe it is not true that only people who write in forum are the ones with complaint. Many others out there may have similar problem but there are many reasons why they do not write in forum, such as:

  1. They feel their problem has been well represented by other posters, hence once there is solution from manufacturer, their faulty device will entitle for the solution too. Why post so many posts while they indeed the same subject?

  2. They may not aware of where to complaint about their problem.

  3. They would rather let go the $$$ rather than spend time to complaint.

  4. They may not aware of the risks of the excessive heat generated by the device.

  5. They may not aware of their rights as a customer, especially those in countries where customer rights protection is weak.

etc…