[SOLVED] Do you need to plug extra ATX 12v 4x4 pin power cables from the PSU to MOBO?

[NadeMagnet69]

My Asrock z490 taichi has 2 of them, so does the corsair 850 PSU. The manual says they are optional. What are they for then? Doesn't the mobo get the power it needs from the main 24 pin? It's a modular PSU so I'd rather not clutter it up if it's unnecessary.

Also when it comes to wiring the GPU is one cable OK? It's an RTX 2080 that needs an 8 and a 6 pin. Saw a youtube vid that says you should use 2 different cables to spread the load. So like 1 cable for the 6 and 1 for the 8? Is that also necessary or can I just use 1 cable since each cable goes from 8pin from the PSU and splits to an 8 and a 6? It seems unnecessary to spread the load.

What if I was running 3 GPU in 3 way crossfireX mode? Then it would have to be 1 cable per GPU. Again, I don't want to rout extra cables if I don't have to. lol I already suspect my cable management is going to look like a joke so I want to make it as easy on myself as possible.

Sorry for the newb questions, this is my first build.
https://download.asrock.com/Manual/Z490 Taichi.pdf

https://www.corsair.com/corsairmedia/sys_master/productcontent/RMx_2018_Manual.pdf

 

[helpstar]

one 8pin EPS/ATX CPU power connector is needed, the other one only if you wanna extreme overclock and use more than one/two GPUs.
To be sure your system will run stable, I would connect the other 8pin connector as well, but you won´t have to.

the PSU is a single rail design so you don´t need to spread two cables to the GPU, only one with 8+6pin connector will suffice.

crossfireX is only available if using AMD cards, you´ve got a nvidia GPU.
SLI and crossfire are dead features, amd and nvidia doesn´t support these anymore

a 2080TI would be a better deal than two 2080 in SLI

View: https://www.youtube.com/watch?v=recJmg0WB_s

 

[NadeMagnet69]

OK thank you. I knew 2 was sli but I didn't know the name for 3 so I thought it was crossfire. Now I see that SLI is 2 or more. I never intended to try it, I just wanted to hear from someone on why the vid said to spread the load. I wouldn't buy a second GPU anyways when it's past time to replace my 8 year old 27inch Korean Shimian monitor that's only 60hz.