Can I replace a ATX motherboard in a Cyberpower PC, with a different more expancive one?

[myaccount1234]

I can get a Cyberpower PC for used $489.99 with a Ryzen 7 1700 and a Zotac 1050 ti 8 gig ram, 450 watt power supply. The motherboard in it right own is a ATX board, so would I be able to say replace it with something better?

 

[USAFRet]

I can get a Cyberpower PC for used $489.99 with a Ryzen 7 1700 and a Zotac 1050 ti 8 gig ram, 450 watt power supply. The motherboard in it right own is a ATX board, so would I be able to say replace it with something better?

Probably.
You should probably replace that PSU first, though.