No Signal plz help!!!!!!! In dire need Only PC son has homeschool . I changed the cpu and added two more 4gb sticks all the fans work and power but I get no signal. HDMI hook up. So I took off all added parts and put old parts back but t had very lil thermal paste, I also noticed the speaker that does the beeps and signals the round part with two wires one wire came unsoldered.After putting old parts back on still get no signal but PC comes and all fans. Any ideas my son need PC for homeschooling it the only one I have I just suffered from a dibetic coma I need help bad someone plz help me asap.