@random_user_101
Note the time when the screen freezes and then look in Event Viewer for any of the above mentioned events, (don't worry about information, audit success or audit failure) and then click (double click?) on the event if any shown at that time to find out more. Then go online and search for the Event ID and Source to find out what it means and why it might be happening.
The GPU card recommended "minimum"power requirement is at the very top limit of the PSU, which is always undesirable with a power supply. You want a bit of a buffer between what the PSU can deliver and what may be needed.
It would be good if you could say temporarily swap in a 600W PSU and then check what happens