Check the boot problems sticky: https://www.raspberrypi.org/forums/view ... 28&t=58151
The 3B+ has USB booting enabled by default. You could try writing a Raspbian image
to a USB flash drive with Etcher
and see if that boots. USB boot is slower, so nothing will seem to happen immediately after applying power, but if you wait a moment you should see the GPU test (color square) and shortly after that the system should boot from USB.
My mind is like a browser. 27 tabs are open, 9 aren't responding,
lots of pop-ups...and where is that annoying music coming from?