The question is why did i fail ? Do you have a multimeter ?
I recently got an US shielded rev 6.2 a2000 with faulty RGB output.
I took off the shield and checked the tracks.
I found a cutted/half burned track and a dead fuse F5 (4 Amp). I rebuild the track with a wire, and pickup the fuse of the serial port...
PS : I'm looking for these little green fuses..
AmigaCenter can also help you, just send the motherboard