ok. After I changed to a new RAM I still had some problems. Then I updated all the drivers, specially the video ones, that seemed to be causing the problem.
After that, I got rid of BSOD but had a couple of screen issues. The screen starts to dissapear behind many colors until it's completely colored like a broken TV screen or something. The pc doesn't hang as I don't see any event.
So, this seems to be a problem of my video adapter or the motherborad because video is integrated on my laptop.
I guess it's a problem of temperature because the couple of times appeared when doing extensive work such as antivirus analisys.
BUT, today I got a BSOD again (strange thing). The only thing I changed is the service pack 3 that I installed yesterday. Could this be causing some problems??
the message of the BSOD was IRQL_LESS_OR_NOT_EQUAL (sorry but I didn't copy the text at that moment):
From event properties:
Error code 1000000a, parameter1 805a399d, parameter2 000000ff, parameter3 00000000, parameter4 805a399d
I'm attaching a zip file with the minidump of today's BSOD.
Thanks