i have recently built a new computer and when i try to start the computer up the screen just goes into standby. I have resolved this problem once before but was still unsure what the problem was. now it has happened again and this time i tried the same thing but it didnt work. the monitor and video card are both working as i have had the computer running once before with both of these and i have also tested them on my other computer. can you please assist me in trying to work out what is wrong with the system so that i can fix the computer if this ever happens again?