Brain fart. The fact that it's not showing anything right for this drive confused me so I thought it showed the slot capability, not the drive.
The Samsung drive is itself only Gen3, and its rated specs aren't much different from the NV2, so theoretically they should perform about the same. The rated speed for the NV2 is 3500MBps reads and 2800 writes, and it should still be able to come close to that at PCI3x4 (the max for that is 4GBps). 1.5GBps is extremely poor performance (just good enough for Gen2 x4) and still points to it being a fake drive.
Here is one review where it was tested in a Gen3 slot (only a 1TB model), which shows what DiskInfo ought to display as well as the performance that would be expected. As you can see, the DiskMark tests look much better than what you seem to be getting, and the other tests aren't as high but are still better.
This SSD was originally reviewed with the Orico PWM2-G2/PWDM2-G2 USB3.2 Gen2 M.2 NVMe/NVMe+SATA Enclosure, but seeing as I now have an M.2 to PCIe adapter, I might as well install it into my main d…
goughlui.com
I did a quick search for "realtek firmware VC2S0388", based on what DiskInfo showed in your original post. Based on the result, I think what you've gotten is a fake drive based on a Realtek RTS5765DL controller. In some cases the fraudulent drives even have firmware that has been altered to make it be detected as the actual brand you expect (such as the Samsung drive Reddit post below), but in your case that seems not to have been done.
It's harder to be sure with a drive like the NV2, since Kingston does actually use controllers from multiple companies, but they definitely would have made the firmware identify it as a Kingston drive AND it would be using a PCIe Gen4 controller capable of meeting the rated speeds, not Gen3. As the review above shows, several review sites received models with different controllers, but they were all Gen4 and none of them were Realtek.
https://www.tomshardware.com/news/fake-dollar39-samsung-990-pro-4tb-ssd-looks-almost-real
Hello everyone , I have been struggling the last few days to see how Chinese Aliexpress “Companies” or “Individual Users” manage to sell fakes , in particular M2 SSD NVMe because a friend of mine got scammed , I wanted to see/inspect how do they make such good fakes some even get detected by...
winraid.level1techs.com
https://devicehunt.com/view/type/pci/vendor/10EC/device/5765
Information about the SSD 1TB data storage device model with firmware VC2S0388 of the Unknown trademark
smarthdd.com
Information about the SSD 4TB data storage device model with firmware VC2S0388 of the Unknown trademark
smarthdd.com
Emag is a "marketplace" where other people sell things and just use Emag to handle the transactions, and I'd bet that the place that actually sold the drive was one of those disreputable sellers, not Emag itself. The same thing happens with Amazon and Newegg in the US, and you have to verify the seller to be sure you're not getting ripped off. (Though even Amazon has gotten a reputation for shipping fake products sometimes now.)