Hello, mestresan,
DO you have any news about it ? I am having what seems to be the same problem. I had for about a year a working 990FXA-UD5 rev 1.1 + FX-8150 , with the last BIOS. Then one day it stopped working. Same symptoms : Fans start, but no boot, no beeps, not even if I don't put video card.
I tried changing memory, slots, video cards, nothing. Until I tried with my old cpu : Athlon II X3 455, that I had, forgotten in a box.
And it worked !!! No problem at all, I even could play Batman Arkham City again and last night Batman Origins (some lag though).
So it was clearly the cpu that died.
Today I went to the store and bought a new FX-8350. Almost US$300 here. I came happy and excited to home...and the same. It does not boot, it doesn't beep, fans start, etc.
Now I think that the old cpu is maybe still good. I almost threw it to the garbage, I found it though.
But I don't know what to do now.
Any ideas ? Somebody ?
I am thinking about booting again with Athlon II and force reloading of last BIOS: Maybe it is corrupt. I know this mobo has dual BIOS, I wonder if the update process left one with the factory BIOS and suddenly it went back to use that.
Best regards,
Luis