4GB cards?

Hey there, a friend of mine is sitting on 7 GT 730s and 3 GT 1030 4GB cards from back when he upgraded people's PCs. He used to use them to mine ETH and offered them to me for $100 per card. I've been looking online for a little while and it seems like some 4GB can be used to mine RVN but others cant? Any info helps! Thanks