I will resume my problem and the solution:
My board is 2.5.2 (not original) and with firmware 2.9 works fine (or it appears to be but it is in danger).
After trying to update firmware from 2.9 to 3.0 or 3.0.1 the problem is the bad gyro health caused because of 5V on 3.3 regulator.
I am engineer so I unsold the 3.3 regulator and checked it. It was ok, but the 3.3v rail is at 5v, even without regulator soldered
Then I tried to replace the regulator for another one, same problem...
I tried to downgrade to firmware 2.9, the board works OK, so I tried to fly and it flies ok (or it apears to be OK, but all the sensors are overvoltage).
After 30-40 mins fly time the quad started to do some suddenly movements (I dont knew whats happening then, now I know it was the sensors at 5V instead of 3.3...)
But now I understand everything:
There is a problem in the board layout, there are a level shifter from 5V of the ATMEGA to 3.3v of the flash memory. The 3.3 and 5v references are inverted. Thats all the problem, nothing from regulators.
SOLUTION: Very hard and complex soldering skills. You must cut wires from the dataflash level shifter and interchange 3.3 and 5v. Cut the blue lines and replace with cable the red lines.
OR maybe you are not interested in use the dataflash but you want to repair your board: It is only necessary to cut the 2 wires in blue and the board will work perfect but the dataflash will appear as disconected.
It is incredible that all the sensors worked at 5v for so long time ago and didn't crashed :o. Also, the dataflash is working at 5V without problems... Incredible!!!
I didnt try to fly yet but the board loads the 3.0.2 firmware properly and passes all the tests.
Mine is working with this change but the problem was the data lines and not the power lines of the level translator. You can check it in the datasheet of the chip.
So if you want to solve this the first thing you have to checkout it is if your pcb has the bad level routing on the dataflash. Definitive solution is very complex to routing but like me you can repair it.