You can solder the two open ends of the wires/base together. Generally, it doesn't hurt at all to have the yellow wire not connected. As long as the fan is still running, you will be fine. The yellow wire gives information about the fan RPM. You just won't be alerted if the fan stops working.
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You can solder the two open ends of the wires/base together. Generally, it doesn't hurt at all to have the yellow wire not connected. As long as the fan is still running, you will be fine. The yellow wire gives information about the fan RPM. You just won't be alerted if the fan stops working.