Acer XF Monitor not getting power. Any ideas on how to repair?

Usually these issues are due to bad capacitors, especially on retail friendly brands like Acer. They often use CrapXon (CapXon) capacitors, which always fail given 4-5 years of use. It’s just a matter of when.

Depending on if the power supply is internal or external, you may need to inspect two different boards. Outside of business oriented Acer models, they have largely moved to external supplies so in order to troubleshoot those you will need a new power brick to see if it persists. If it doesn’t consider yourself lucky - outside of a lucky few it never fixes anything and is only done to save space at best because it’s usually always internal.

If the problem isn’t fixed, then you need to work on the internal boards. Usually these snap together where the whole back comes off, but I’ve seen a few designs where it appears the board and panel access may be split. Since these have become more common, use some common sense until you know for sure. From what I can approximate with the device page model, it looks like the entire back needs to come off as a single part but it may be split and it’s an internal power supply type.