What kind of PC did you build? Operating system? Motherboard/Processor type/RAM/Power supply info/monitor type, plus any other information you can think of.. What have you tried in order to fix the issue? Swapped in another monitor? Did you install all the drivers after installing the operating system?
Hope this helps and let us know more.
i already built a new pc..when i turn it on,nothing's happen in my screen.i also cannot turn it off,i have to turn it off using the switch in psu..so..what's the prob?