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[SophieTheMeh]

I just built a new rig but I kept my old GPU and im currently using an old HDD to download windows onto my new one (haven't gotten to it yet) when I turn on my PC the fans start up but nothing shows up and the lights on my mouse don't light up either. It turned on fine one time and I went to turn it off and reboot (turned it off correctly using the windows power off thing) but it now refuses to show anything. Could it be my GPU?

 

[rgd1101]

full system spec? include make and model of the psu