I just registered to share my success. I had these problems w/ my Aspire 5135 and tried all the suggestions with no joy. Finally, one year later I thought I'd give it one more go and had success! From a brick to a perfectly working laptop again! I can't post links so try it out:
forum.notebookreview.com/acer/284686-aspire-5315-bios-recovery-using-usb-thumbdrive.html
Good luck!