That bad, huh... I would assume that metal casing on a flash drive is a good thing as it would offset heat from the circuit board. And moving files is only temporary, once your flash drive becomes idle, it would cool down. Has this happened since you bought it?
Yes, drive itself is working kinda properly, i haven't noticed it to be thermally throttling. To be specific this is the drive:
Combine the necessity for a convenient way to store and move your data with your desire for a protective, elegant device. With fast transfer speeds up to 150MB/s1, the all-metal SanDisk Ultra Luxe™ USB 3.1 Gen 1 drive can transfer a full-length movie in less than 30 seconds2 so you can spend...
shop.westerndigital.com
Bought it around year ago, never seen on it these usb3.1 speeds no matter if i plug it to 3.0 or 3.2 ports i have on my motherboard (x570 taichi). I even considered demanding a refund from amazon because of speeds but i bought it in bundle with other stuff via my gf's account, let's put it mildly i do not have access to that account anymore.
On recent black friday deals i found in one of local online stores samsung 128GB 3.1 drive for (converting, around) 15,5eur. It also has metal casing and will check if it reaches at least usb3.0 speeds. To be honest i've not seen yet a usb flash drive with file write speeds over 10MB/s, would be nice to finally get it. From what i've read about that samsung drive it should have proper speeds. Actually i do not care much about speed but well... As for samsung this is the drive i ordered now:
Discover the latest features and innovations available in the USB 3.1 Flash Drive BAR Plus 128GB Champagne Silver. Find the perfect Memory & Storage for you!
www.samsung.com
Mine fried itself... So I took it apart. The reason it's hot, is because it uses a basic SSD controller and an Asmedia SATA to USB 3.0 bridge chip.
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I got another one, as I had some airmiles I had to use up, but seeing this, it seems like either the firmware is wonky, or the replacement drive has some serious problems.
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Interesting find, amounts of unnecessary conversions some manufacturers use in hardware is mindboggling. Thanks for sharing that.