I have an HP desktop M7680N, it willnot detect my screen nor my usb's. my monitor is good and my usb devices are good too. i have to keep turning it on and off until it suddenly works but as soon as i try to restart it, it does the same thing. can anyone help me with this? thanks!! What happened before the problem? What were you doing? (+downloads/installs/hardware changes/ect....)

What OS is this?

Any error messages?

Any beeps?Do you get any image on the screen at all?
Like the HP screen before windows loads.I have not made any hardware changes and I have not installed any software related to the system management, the only software I have installed in it is VIDEO games. I'm running XP, idon't get any errors and no beeps either. Before the system loads the screen just says "no input signal". I disconnected the screen from the pc and it told me I need to check my video cable. according to other people this means the screen is fine. I connected my other monitor and it did the same thing. so i know that it's not the monitor.
my usb components such as the MOUSE and keyboard are fine. As I said my computer will work fine if I keep pressing the power button on and off. thanks!! I would borrow a PSU of the same or greater wattage and swap it in there to see if it is the culprit...
Is this an eMachines by chance ? ?no, it is a HP Media CENTER M7680Ni purchased a new power supply and it still does not work. I ASKED my friend for help and he told me that my computer does not get to POST which he told me it means that my computer did not scanned for any hardware. do you think this is a motherboard issue?ive had PROBLEMS similar