computer was doing good then after a day, when i turn on the avr, as usual the mobo led(green) lit, and as i switch the cpu on,red led on power lit, as well as the green led on CD-Rom, monitor turns on but after a few seconds, the monitor green led turns into orange and it displays no signal, no beeps, red led on power stays on, as well as the green led on cd-rom. all fans are working as well... what seems to be the problem? i already checked the memory cards and the hd and it's working well on the other pc. please help me, what should i do?