O que vem primeiro: As Crônicas de Sarah Connor ou Terminator 3?

Não há causalidade entre os dois, ambos ocorreram em linhas de tempo separadas e independentes.

Então, eles acontecem em linhas do tempo separadas e não estão relacionados entre si.

Em termos de datas, o TSCC aconteceu primeiro. O TSCC começa em 1999 (mas eles viajam 8 anos no futuro até 2007). O T-X de T3 foi enviado de volta para 24 de julho de 2004

Houve algumas especulações de que os dois cronogramas podem ser forjados juntos . Por favor, tenha em mente que isso é pura especulação, e de forma alguma evidência de cânone.

After the events of Terminator 3: Rise of the Machines the war starts between humans and machines. John becomes leader of the resistance. Skynet manage somehow to make advanced robots earlier than the previous timeline (maybe from the remaining parts of the T-X and T-850), which lead to creating the "Cameron"-model and using it on the battlefield. After the previous attempts of killing Sarah and John Connor (T, T2 and T3), the war still goes on, and it's getting tighter. Skynet now use all resources on the battlefield. In a last effort they send a T-888 (an older model) back to 1999 to kill John Connor. As a counter attack, the Resistance are able to catch a terminator from the battlefield (a "Cameron"-model) and send it back to protect John Connor. Sending terminators back before the previous timeline results in "erasing" the Terminator 3: Rise of the Machines-timeline completely (or, alternatively, creating a separate parallel timeline).

Josh Friedman, o produtor de The Sarah Connor Chronicles abordou este ponto em um entrevista com a IGN em 2007.

A versão curta é que o TSSC ocorre em linha do tempo alternativa , o que significa que não há continuidade entre ele e T3.

IGN TV: Are you working within the continuity of the Terminator movies, specifically Terminator 3?

Friedman: We're gonna go off on our own. I think the thing about T3 is, obviously there was just no Sarah Connor and that's something the fans were never happy with. I don't even think the people who made T3 were happy with that. It just wasn't a choice of theirs. You know, Linda Hamilton was going through some things and didn't want to be a part of it. They had a script at one point I know; there was a T3 that had Sarah in it. I've never read it. I don't know anything about it. But I know that they did and they wanted to do that. They wanted it to be kind of her trilogy, and it never could be. So I think that my feeling was this TV series to me sort of serves as the third act to that trilogy - what could have happened had we followed that after T2. So I almost think of this as T3. To me it takes the place of T3.

But also I think that sort of in the spirit of Terminator, it's an alternate timeline. I know a lot of people get very worked up about the continuity and the canon and all that stuff. What I try to do is stay very, very true to the first two movies and then sort of take it from there. But always remain true to the spirit of everyone's intent and again, take some time with this woman and explore what maybe would have happened.

Bem, linhas de tempo alternativas e loucura envolvendo viagens no tempo, tecnicamente falando, o SCC está antes do T3. Só que os eventos de T3 no cronograma do SCC aconteceriam mais no futuro e mudariam muito.