If you have more then 1 GPU, like say you have 2, you will need to SLI them together with an SLI cable to get them to work together on the same program or software. Now here is the misunderstanding. SLI 2 cards together will not double your Vram. Meaning if you have 2 cards, a 1.5g Vram, and another 1.5g Vram, they will not act like a 3g VRAM card, only the 1.5g will count. it's the CUDA cores that get added together. Another big thing to note, not all games or programs support SLI equally. Some games may not work as well with SLI, meaning that you won't get a true 1-1 ratio in the cards adding together. if you have a 1000 CUDA core GPU and then another, they may not add to a full 2k CUDA count for that program, it may even only hit 1.3k count on some programs. My personal opinion, at this time, and I may be wrong, But I find it better to buy 1 big card and not 2 medium cards. Hope this helps with GPU purchase decisions!
Common SLI Misunderstanding
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