Old pc won’t work

Hello, I am in need of some help, I have tried for the past several months to get and old server pc with some valauable info on it to work I have replaced psu and that seem to help because now it stays on but it keeps running the fans and hard drive seems to work and motherboard light is on but I plug the vga cable in and there is nothing on the monitor I’m lost and dont know what to do now so I found this anything helps
Thx