no no, i dont have 2 GB Cards. i have 4 cards (1 of 8GB, 3 of 4GB)

currently i have a rig with 3 cards (the first card in Main PCIe is 8 GB, and the other 2 cards, 4 GB)

Next, in my main PC have the 4th card with 4 GB, this card dont works. But the question is why the other rig works fine? from the 3 cards, only 1 is of 8 GB, and are minning the 3 cards