iMac Will Not Start Up Properly

My iMac had been working fine for years, but after deconstructing it to upgrade the full-size RAM stick, it will not boot up again. When I press the power button, nothing happens aside from a small clicking noise from within the computer.

I've already tried reverting back to the old RAM stick, but that didn't seem to change anything, which is a bit worrisome. I've also attempted a few of the go-to tricks, such as a PRAM reset and the 10-second power button hold.

When I took it apart again, I noticed that the internal wires coming from the power cable input slot were stripped of a bit of their protective coating, likely from getting pinched during the process of putting the computer back together. I'm not sure whether or not that makes a difference, but I suppose it's worth mentioning.

Any ideas or suggestions are greatly appreciated.

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