Start from scratch or repurpose year old Dell Optiplex?

Hey everyone. I’ve been learning more and more about hackintosh setups and I’m thinking I’m ready for my first build.

My questions is would I be better off starting from scratch and building everything from the ground up (minimalistic case, i5, 8GB, AMD video) or using a year old Dell Optiplex (i5, 8GB Ram, 4GB AMD video card) as my base? If I build from scratch I would have roughly the same specs but I wasn’t sure if you could set Catalina running on a 5030.

Any input would be greatly appreciated!