^^ it's highly unlikely that the replacement unit is bad - tell that guy to check your pc ( sand gfx card ) with some different PSU ( even a cheap one will do ) and which wire you are talking about exactly ??
he did check it with a different psu and it worked..the green light on the motherboard lights up when i switch on my ups, but the computer doesn't start...and see the picture for the wire..
is it possible that something else, not the psu is responsible?