System failure detected, CPU warning appears briefly, memory issues triggered
System failure detected, CPU warning appears briefly, memory issues triggered
I believed you were referring to a PCi port, but the HDMI worked with both the motherboard and GPU. I think I should check that. The 450W usage would exceed the total power draw of all components. Regarding BIOS updates, it's possible without opening the BIOS menu.
Some boards struggle to display images on the mainboard output when a GPU is installed. This might indicate the GPU isn't functioning properly, which has occurred before. It's possible, but you should take it to a specialist who understands these issues. You'll likely need an EEPROM writer, and if the chip clamp isn't suitable, a hot air station may be necessary. A tech-support shop could provide another CPU for testing in the setup.