Question Potentially unusable/ruined RAM?

[bobthebuilderr]

So, i got a single ram stick (not knowing i need 2), and want to buy a 2nd one so i can use those in my PC.
But i noticed this on the contacts:

https://imgur.com/a/scf5lAC

View: https://imgur.com/a/scf5lAC

Does this make it unusable? I dont want to buy another without knowing if itd be a waste or not.

 

[The Paladin]

https://imgur.com/gmvRbUm

Well this close up shows a portion of the contact itself is missing, why this happened, could be answered a number of reasons which is pointless right now.
if you put the ram into your computer does it boot up? then I would get MEMTESTx86 reboot with thumb drive and test that ram for all diagnostics, why ?
Well if there is enough of a contact for the ram to process data properly with computer then it is a non-issue, get another stick that matches it and enjoy your upgrade, but if it fails the tests then you know you need to get 2 sticks of ram and not use this one

you can get MEMTESTx86 from https://www.memtest86.com/

 

[bobthebuilderr]

https://imgur.com/gmvRbUm

Well this close up shows a portion of the contact itself is missing, why this happened, could be answered a number of reasons which is pointless right now.
if you put the ram into your computer does it boot up? then I would get MEMTESTx86 reboot with thumb drive and test that ram for all diagnostics, why ?
Well if there is enough of a contact for the ram to process data properly with computer then it is a non-issue, get another stick that matches it and enjoy your upgrade, but if it fails the tests then you know you need to get 2 sticks of ram and not use this one

you can get MEMTESTx86 from https://www.memtest86.com/

Thanks, i did that and it seems to be working.
And i think i mightve been using that instead of the 2x4GB i had so far... because i kept the 1x8 in there alongside the 2x4, and i thought it was just ignoring the 1x8, but it mightve been just using that (even tho i have some vague memory of checking and it using the 2x4)
But now it seems that one of the 2x4' s is not usable (4 beeps when in there alone).
Could it be that at some point, one of the 2x4's malfunctioned and the PC automatically switched to the 1x8?