I presume you are talking about the cord from the wall outlet to the PSU's rear input socket. If you are using it in a place that has 125 VAC standard power from the wall, then the 125 VAC cord is sufficient. The PSU, like many today, is designed so that it CAN accept power from the wall outlet anywhere in the range from 110 VAC up to 250 VAC, and it will adapt itself to deliver the right power into your computer. Such PSU's often come with a power cord rated for 250 VAC in case that is how it gets used. BUT as long as the power from the wall is in the 125 VAC range, the cord with that rating is OK to use.