very common symptom esp when either the motherboard has shorted or the psu is faulty

this is bcos you can see some led but no motor movement on the fans

fans need power and the power is drawn fr the psu through parts of the motherboard. its not the cmos batter bcos the symptoms of depleted cmos battery is beep wanings at bios boot up time - in your case it cant even get to that bios boot up session bcos there is fundamentally lack of AC juice going into your machine

change part by part testing one thing at a time - start with a psu then motherboard - though i think these activiews are best done by a pc tech with you supervising like a hawk