Help Pls! Replacement power supply board/Magnavox LED TV didn't work, no power

[Tricia0723]

I have no knowledge of electronics, let me say from the get go! But, I'm tenacious enough to research, order parts and give almost anything a try. I did successfully replace the "other board" on a different TV (where all the ports are), so it only emboldened me to order a power supply board and replace the existing a smaller, older TV. The red standby light will stay on, but TV won't power up anymore after intermittently working. I was advised to replace the PSB. Apparently, that's not the problem, and I really don't know what else to try. TVs don't grow on trees, so I really hope someone can suggest a simple fix. It seems a common problem. Thank you all!