One of my systems is an x58 board with a xeon x5660 on an asus px586d-e board, did have crossfired 7970's in there until just recently. Even with the 7970's, it was an ok machine for gaming, but I definitely wouldn't build one in 2020, even if you can do so for a $300 or so... It's a power hungry platform and it's showing its age in many tasks. eg. Compiling a mid scale java ee application on my work 3700X takes about 7 seconds and takes about 40 seconds on the x58 system. Things have simply moved along too much to be worth spending any money on the platform unless you want to build a gaming system to run on your 60Hz 1080p tv.
I put a 1070Ti in it and it does perform nicely for gaming at 1440p 144hz, but it's a bit of a waste in many situations.