Yes, it is safe to use a 4+4 connector.
Yes, it is safe to use a 4+4 connector.
This might be a new question, but is it safe to use a 4+4 connector split between two different CPU power slots? Your motherboard has two CPUs that need power, and the total power demand is around 123 watts. You're thinking about extending one of the pins to connect to the second CPU slot.
The 4-pin setup works just like the 8-pin version, with the main difference being extra power capacity. As long as the current usage stays within limits and the supply can handle it, everything is fine.