[robespierre]

That is what is known in the trade as a "bodge wire". It is a rework to the board usually done at the factory as part of a repair or ECO (engineering change order).
As to its purpose I can only guess, but it does connect near to the Dallas Timekeeper, which as its name implies keeps the system time when power is disconnected, but also holds the boot variables and can power the machine on at a specified time.