It has to be analog at some point my man. I have never seen a soundboard with a built in A/D (but they do exist). You're going to need a cable that can take either 1/4" or XLR or RCA (preferably all three just to be safe). Then you can use some pigtail adapters to get it down to 1/8" stereo mini and plug it into your sound card.
As others have said, don't worry about a TOS-to-RCA. You can do TOS-to-Digital Coax (which looks like an RCA plug but is digital-audio) but that will gain you nothing if your source is analog like a sbd feed is. You will be best off getting either 2x Male-XLR --> 1x 1/8" Phonoplug and run that as a line-in to your laptop. I carry one of those and also (2) XLR-Male --> RCA-Female adapters and a longer 2x RCA-Male to 1x 1/8" Phono.
The cheap way would be buy two XLR-Male --> RCA-Female adapters, two 1/4" --> RCA-Female adapters, and then a 25ft 2x RCA-Male --> 1/8" Phono cable. That way your adapters can cover all three most commonly used ways to patch a board and you only have 1 cable which is relatively cheap to buy.