It's possibly just some electrolytic capacitors on the main board or PSU that have gone out of spec or completely failed. Look around for capacitors with a popped out top.
Finding a motherboard with an 11 year old socket shouldn't be hard, unless it was a really obscure socket. Looking up the Intel socket I had in 2011, for example, yields plenty of options on Newegg.
Finding a motherboard with an 11 year old socket shouldn't be hard, unless it was a really obscure socket. Looking up the Intel socket I had in 2011, for example, yields plenty of options on Newegg.