I use an older iMac as a movie and photo server for a whole-house system and a few weeks ago it took its final breath...or so I thought!! Researched everything I could that described the symptoms I was having and finally landed on the power supply as the culprit.
Repair went flawlessly. Having watched the video before I even ordered the part, I was already equipped with the knowledge to be successful in my diy repair.
Don't be afraid. You've got this!