As I understand, memtests are designed to reveal the issues with RAM. The pages on Aliexpress for similar diveices (at least the Topton ones) warn than not all RAM and SSD are compatible with such motherboards. That's the reason people here share the exact SKU numbers for SO-DIMMs and SSDs. I risked with Apacer SSD no one tried before and got lucky.
There are at least two possibilities in your case:
- RAM module is faulty (it happens, though rarely, that maybe this kind of luck)
- This particule module or the SKU in general has compatibility issue with the MB (some chips are picky to the MBs)
Test the RAM module on another machine, even better on several different. Or return the chip to the seller as a faulty one with screenshot of failed memtest (they normally should test it for a decision). Or Buy another one that was mentioned in this thread, in this case you have untested spare RAM module for future endeavors.
Personally, I have encountered issue with RAM once, but the RAM SKU was cheap (perhaps noname, don't remember) and MB was MSI or something (not top hardware, it was long time ago).