Chosen Solution
My system worked fine recently, but today I powered it up and the BIOS screen wouldn’t show up. I disassembled the system, and all the inputs seemed to be soldered correctly. Is there something I might have overlooked, or might it be something related to the A/V cable? (The cable is an RF modulator cable, by the way.)
There might be something really wrong with your motherboard. Take apart the console and check for grime, dead or corroded caps, and corrosion. Maybe check the CPU/GPU?
