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I have a cheap USB flash drive here which is marketed as USB 3.0, has the typical USB 3.0 blue plastic, but only comes with the classic USB 2.0 four contacts on the inside and has speeds in the USB 2.0 range.
Is there anything in the USB 3.0 spec that allows that configuration or is that simply a fake?
Grumbel
Posted 2019-08-16T13:09:36.590
Reputation: 3 100
21
It could be a fake. USB 2.0 only requires 4 pins, but for the bandwidth of USB 3, you need the additional 5 pins.
However, make sure it doesn't have those five pins. They can be hard to see, and they wouldn't be visible on the angle your picture has.
On the female end, you have the five pins right up front, on the male end, you have the five pins shoved in the back. They're small and hard to see.
EDIT: According to telcoM, you might be able to technically call it USB 3, if it's getting some protocol improvements that can be applied to USB 2.0 and lower speeds. Can't say for certain if that's the case here, and it also wouldn't matter since it'd still be limited to USB 2.0 speeds.
So essentially, for most use cases, it's just USB 2.0, however it might have some protocol differences that technically allow them to call it USB 3.
USB 3.0 Female
USB 3.0 Male
udlp
Posted 2019-08-16T13:09:36.590
Reputation: 450
Added another picture from a flatter angle, definitely no sign of those five pins. – Grumbel – 2019-08-16T13:35:08.520
18Yeah, seeing the new picture, no way this can pull off USB 3.0, it's definitely a fake. – udlp – 2019-08-16T13:48:30.160
7It could be technically not a fake, but also "not USB 3.0 in the sense most people care about", i.e. speed. The USB 3.0 specification also includes some protocol improvements that can also be applied with USB 2.0 and lower speeds. Implementing those can be essentially just a firmware change, and allows marketing to legitimately claim "USB 3.0" as long as they don't also claim "SuperSpeed". This is a case of "let the buyer beware" essentially built in to the specification. – telcoM – 2019-08-17T07:47:07.967
@telcoM: Would such a device show up as being connected to the USB 3 host controller or the USB 2 host controller (e.g. in lsusb or Device Manager). – R.. GitHub STOP HELPING ICE – 2019-08-17T18:10:33.400
On new systems and chipsets, there is no longer a separate USB 2 host controller, only the XHCI USB 3 host controller. However, there will still be two separate buses: one for the devices capable of 3.0 SuperSpeed or better, and the other for the slower devices. A non-SuperSpeed "fake USB 3.0" device would absolutely appear on the slower bus, together with the other slow devices. – telcoM – 2019-08-17T20:09:08.183
Edited to add what you're talking about. If I misunderstood at all, feel free to edit my answer. – udlp – 2019-08-19T00:25:41.487
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This is not a fake, but a cheap and ugly marketing trick. USB 3.0 specifications are backward compatible with HS, FS, and LS data rates. So formally any USB device can be called "USB 3.0 device running at 480 Mbps data rate", and it would be not illegal.
For example, there are plenty of MCUs on the market that say having "USB 2.0", and only reading deeper into specifications you will find out that the USB interface is "running at FS (12 Mbps) rate".
Ale..chenski
Posted 2019-08-16T13:09:36.590
Reputation: 9 749
That is fake though. You cant sell someone a Ferrari and say "Well its not actually a Ferrari but it works on the same roads". – Qwertie – 2019-09-05T03:45:09.980
3If it's too good to be true, it most likely is ;) – CustomX – 2019-08-16T13:30:24.917
3I don't believe the color of the connector is specified in the USB standard. Razer for instance uses a green connector on their USB devices. – Ramhound – 2019-08-16T18:28:58.460
4Was it specifically advertised as USB 3.0 SuperSpeed? – chrylis -on strike- – 2019-08-16T23:00:08.207
1And that's why you only buy sticks from the bigger companies. There are plenty of larger USB 3.0 sticks available from them at 0,10 - 0,20 Eurocent per GB. Don't bother with the cheap ones, they're not up to spec so not as fast as you'd want. – Mast – 2019-08-17T08:58:30.947
This is fake. Be sure to check if its size is real, if isn't, refund it/write a review wherever you bought it from. This is the best way to fight back. (apart from nukes launched from orbit of course) – Nyos – 2019-08-17T14:25:43.840
2@Ramhound the USB spec recommends blue for USB 3, to make it clear if USB 3 is supported. But it's not required, and a lot of laptops (at least) seem to just use normal black USB ports to avoid the blue messing with their style. – Ian D. Scott – 2019-08-17T20:03:28.697
@IanD.Scott - I don’t doubt its a recommendation but not requirement. – Ramhound – 2019-08-18T02:31:42.857