|There have been many previous posts concerning this type of problem and it is almost never a monitor problem. In fact you have already proven the monitor is fine.|
That there is no video output could mean failure of your graphics card but it may also be partial powersupply failure, motherboard failure, Processor failure, Ram failure or some other device such as a faulty optic drive or even another faulty PCI device.
The way to begin diagnosis is to strip the system down to barebones. IE disconnect all power and data cables to harddrives and optic drives. disconnect any USB devices. Remove all but one stick of ram. If you have onboard graphics then remove any VGA or PCIe graphics card.
Leave only Motherboard with CPU and heatsink & Fan, Powersupply, 1 stick of ram, Graphics and keyboard.
Try to power up. Do you get any beep and/or display on monitor? If not then remove remaining ram and try booting without ram. If still no POST beep then you have narrowed the fault to either powersupply, motherboard or CPU.
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