As I wrote in my previous post, I have had uninstalled and reinstalled the Realtek High Definition Audio Function Driver
alrerady (and from the same link of your post), but I still had BSODs, so I finally uninstalled the driver and disabled the onboard audio, with more BSODs (not related to RTKVHD64.sys, but they are in the BSODs "pack" I posted).
Now I am in a new situation and I think I am approaching the cuse of my headaches: with all the parts on the test bench and a new fresh and clean installation of Windows 7, with the latest drivers
I have collected thanks to this thread, and with all the updates installed, the system seems to be more stable.
In the last 24 hours, there have been only a couple of problems: yesterday the system restarted suddenly, with no BSODs or more information. When the system is cold (I mean, after some time being off) and I start it, there is a long beep before the usual short one (the motherboard user manual says that combination of beeps points to a memory or motherboard error), but if I only restart Windows or I start it when it is still "hot", I have only the short beep. And the last and more dissapointing one: a new BSOD today; ok, only one in the last 24 hours, but I'd like to know if it points to something specific because I think the solution is nearby.
It seems that everything points to a kind of short circuit or something similar in my original case (I'm still trying to find where) and I'd like to know how to check if this has affected any of the components of the system, but my priority is to find and remove the cause first.
Here is the last report, and thanks for the help again: