Kernel Panic on startup

Hello!

A while back a customer came to me with he's imac that did not turn on. After troubleshooting i found that the power supply board was broken. I ordered a new one and replaced the old one. Now the mac turns on but it instantly goes to kernel panic mode.

I have also added a link to a video for people who never saw this happen before.

https://www.youtube.com/watch?v=m9JFZ7jq...

I know there has been posts about this before and i've read many of them but i still want to see if there is any other knowledge about this out there. So my following quesrtions is this:

1. Is it possible to buybass?

2. What is the best way to troubleshoot this(and hoepfully easiest)?

3. What causes the errors that make the kernel panic.

4. Anything else ?