Dell optiplex 9020MT psu 24 pin to 8 convert

[Fawiko33]

Hello Everyone,

I have a Dell Optiplex 9020 MT which I would like to upgrade psu due to upgrading the GPU.
It has a Dell standard 290watt power supply model :290AM-00 and it came with a 8 pin connector at the sate of 20/24 pin.

I purchased a PSU Corair Cx600 this one has a 24 pins cable. I even contacted dell for a alternative power supply they only have standard psu.

Is their someone who can help me convert from to 24 pin to 8 pin ?
I tried to figure out with a mutimeter but I really didin`t figure out very well.

I upload some pictures as example. any help will be appreciated