Question 24 Pin PSU connector to weird 10+4 pin lenovo motherboard. (help!)

Sep 8, 2021
I have this desktop tower:

I wanted to upgrade to a better GPU, so I ordered a secondhand 970 and a CV450 PSU to power it (to upgrade from the 250w PSU that came with the tower)
I saw ATX on the connectivity for the PSU and Motherboard, so I naively assumed everything would work.

Turns out my motherboard (Lenovo Skybay... I think) Has a 10 pin connector and 4 pin connector on the opposite side (pictured)

^^ The Motherboard is connected to PSU by 10 pin & 4 pin ATX, and everything else is powered from the motherboard.

I've asked about this a couple of times and people have sugested getting a 24 pin to 10 pin PSU cable connector and filling the 4 pin with another spare 4 pin conector that comes with the CV450.
To do this I would need to get something like this (I think)

Some people say this solution will work fine, Others say something about my motherboard running on 12v exclusively, and the 24 pin running on 5Vsb (I'm not sure what this means)
One person said that the connector would convert the 5Vsb to 12v, but it looks way too puny to do this.

Will the connector work? what does 5Vsb mean? Is it even possible to make this combination work with my weird motherboard?

Any Help is appreciated.
mainboard youre using is using only 12V from PSU, 5V and 3.3Volts are taken from can convert any PSU to be 12V only, or you could get ATX12VO PSU (that will draw much less watts from wall)
but since you already got your PSU, then you just need 24pin to 10pin connector which will carry 12volts your mainboard needs

5Vsb means 5volts