Hi Fredrik,
I am Dave, I will help you with this.
1
That F1 boot error indicates an error in your BIOS, did you replace the CMOS battery with a new one?
Boot your PC into BIOS, find the option to restore defaults, and apply that setting, save and exit BIOS.
2
If that does not stop the F1 screen
Disconnect your Pc from the mains electricity
Press and hold the power button on the case of your PC for 30 seconds
Wait 10 minutes
Then reconnect to the mains electricity and start your PC, do you still get that F1 screen?
3
With regards to the black screen with cursor when booting into Windows are you able to boot into the Recovery Environment using the steps below and if yo can, which of the recovery options have you tried and what was the result?
Start your PC, just as Windows attempts to load (spinning dots), press and hold Power Button for 5 - 10 seconds to perform a Hard Shut Down
Do this twice
On the third start Windows will boot into the Recovery Environment and from there you can access System Repair, Safe Mode, Command Prompt... etc.