I turn on the desktop

Hi jiheeahn! I wiull be glad to assist you. lets isolate the issue. The reason why the monitor says no signal input2: hd15 got to power save. the connection from the monitor to the desktop computer is disconnected or its not connected to the right input connection on the back of the desktop computer. please check the connection from the monitor to the desktop computer, all connection should be hand tight. Then restart the computer, once the computer restarted on the booting process you should hear a beep sound. and display will pop up on the monitor, if still there is no display from the monitor, try to connect a different working monitor to the desktop computer. If the problem still exist, there is a possible problem with your video card, turn off you computer, unplug the power of the computer to the wall outlet and open the your computer in order for you to see the mother board, look for the video card, remove it from the motherboard and try to clean the gold plated part, the contact were you snap it to the motherboard, rub the gold plated part with an eraser (steadler) in order to remove the dirt that is stick on the contact, then insert the videocard back to the board make sure that its sitted on the slot. then connect the input cable from the monitor to the videocard input and turn on the computer, this should fix the issue, if the problem still exist, replace your video card..