Same Model Number, Different Specs.

[aApple2c4LifeDOgg]

I think i can guess the answer to this but ive noticed only recently that a GPU can have the same number, but have radically different specs.

Example.,
Rx 570.

If i go on Newegg  I see offerings of this card from around 100$ to 300$, same 8g, seemingly same configuration.

What im guessing is the 570 only the actual GPU chip, i assumed they would alll use the same DDr5 ram too, now im not sure, maybe cheaper ones don't use Samsung ram? They all seem to have the same copper tubing and 2 fan arangement, now im thinking that might be different going from say MSI to.....i dont know....Gigabyte,
What else can be different? Mine Overclocks to 1550 stable enough so far, but a 570 4g I bought a few weeks ago wouldn't go over 1400 or stable, I understand that there are always differences in manufacturing from one chip to another, but that seems like a big jump to me.

Just Ordered a refurbished 2060, and now im concerned its might not be as good as it can be.

Up til now I play at 1080 so something like an overclocked 570 was just fine, but  Im just getting my VR set up (i have to play ALXY), and that seems like a good all around budget card to go with my 450b ryzen build.

So, help a re-noob out, what's up with the huge price diffferences?

One more thing, before I got the MSI 570 8g I had a XXXXwillnotslanderXXX 4gig, my PC saw it as 3g, any idea why?

[Neutraliz]

Mainly, it's cooling performances & noises that gonna differ from a model to an another. 
MSI's ARMOR RX 5xx is pretty crappy. 

For overclocking, the model doesn't really matter ( if cooled properly ), that's just luck, or lack of. It's the sillicone lottery, purely.