Question PC won't turn on - keeps restarting. Now monitor isn't displaying.

[NyanAngel]

My HDD is faulty so I decided to unplug it. I installed windows 10 on my ssd and I didn't install the hard drive onto my pc but it was plugged in. Once I unplugged it while the PC was off, I turned it on and it showed the error message "Reboot and Select proper Boot Device". I went into the bios and made sure that the ssd was checked (the only options were the ssd or disable) and it still didn't work. I reset the UEFI to default and it still showed the same message. After a while of trying to make sure everything was plugged in properly it didn't start anymore. Only for about half a second then it would shut off and repeat. I've plugged the hdd back in and it still doesn't work. I don't understand what's wrong. I can't get it to start up.

I've tried to start it without the hard drive and the ssd and it still kept restarting. Disconnected the GPU, still restarting. Disconnected the ram and it started for a bit longer but still restarted. I put everything back and it still wouldn't start up properly and would keep restarting. Now the display isn't working (the monitor is working fine just not connecting to the display) it says no signal. I tried switching the DVI cables and it still didn't work. I put in some more thermal paste into my CPU and nothings changed. I tried plugging the DVI cable into the motherboard and it still wouldn't connect. Do I need a new motherboard?

 

[CountMike]

My HDD is faulty so I decided to unplug it. I installed windows 10 on my ssd and I didn't install the hard drive onto my pc but it was plugged in. Once I unplugged it while the PC was off, I turned it on and it showed the error message "Reboot and Select proper Boot Device". I went into the bios and made sure that the ssd was checked (the only options were the ssd or disable) and it still didn't work. I reset the UEFI to default and it still showed the same message. After a while of trying to make sure everything was plugged in properly it didn't start anymore. Only for about half a second then it would shut off and repeat. I've plugged the hdd back in and it still doesn't work. I don't understand what's wrong. I can't get it to start up.

I've tried to start it without the hard drive and the ssd and it still kept restarting. Disconnected the GPU, still restarting. Disconnected the ram and it started for a bit longer but still restarted. I put everything back and it still wouldn't start up properly and would keep restarting. Now the display isn't working (the monitor is working fine just not connecting to the display) it says no signal. I tried switching the DVI cables and it still didn't work. I put in some more thermal paste into my CPU and nothings changed. I tried plugging the DVI cable into the motherboard and it still wouldn't connect. Do I need a new motherboard?

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