you don't need any power when hibernating you only need to keep power there if you use standby.
Iím using an inverter with a diy startup/shutdown controller.
It triggers the pc to hibernate.
Can I use an external 5V power supply to power the standby pin on the motherboard while the inverter is off?
If you don't want to drain your battery yes its the better solution. Standby is faster but uses power.
I want to use standby. I think the 5V on pin 9 is to keep the memory powered. I also see that pin 14 is 5V when the pc is off or in standby but change to 0V when it is on.
Can someone tell me the amount of current needed in standby.