You need something like this, I assume - it's a standard computer power cable:
You should be correct about the voltages being fine. I haven't had to do it yet myself (my desktop computer is in storage with the rest of my stuff) but that is the theory. If you're particularly worried about it, you can get the model number off the power supply for the computer and the monitor model number and look it up.
The monitor is probably ok without any sort of converter, just a new cable (I assume it has one that can be removed like most monitors, but it may be a built-in one, in which case you'll need a plug adapter). However, I'd suggest you get the model number off of it and double-check, just in case.