Got an old pc for one of the kids. I had to renew the P.S.U . Now I'm getting the " No connection check signal cable " when I switch the monitor on. It sounds like the machines firing up. Green light on Hard drive, fans etc. Any ideas.
Does your graphics card if indeed there is one have its own power supply and could you possibly not have connected it when you replaced the PSU, don't mean to be funny but it is easy to do this kind of thing.
I've checked the monitor by connecting it to my laptop. No switched on enough on adding second monitor to laptop but You see the windows start up screen on the external monitor but when it gets to the log onn screen it switches back to the laptop screen.
I don't know if seeing the startup screen is enough to dem that the monitor is working