Question Ram slots question

Mar 4, 2019
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5
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Quick question:

My motherboard (ASRock B450 Fata1ty) has 4 ram slots. I have 2 of the same RAM sticks and I’m not sure which slots they go in. There’s the 1st slot as A1, 2nd slot as A2, 3rd slot as B1 and 4th slot as B2.

Could someone tell me which slots they go into first?