So my computer fell over last night and now it doesn't display anything on the monitor. It turns on then off immediately and then turns itself back on by itself with no display. I tried using a hdmi port but that didn't work either so it's not the monitor. Also my usb mouse isn't lighting up so it seems like any external connection to it isn't working correctly. I opened it up and all lights and fans are running so I'm unsure what could be wrong.

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