How to solve nvlddmkm blue screen problem?

What is this: " nvlddmkm" ?  It is not an error message, so likely you have a root kit virus.

i would start by updating the video driver for this pc

but i must say, a bit more info could help a lot :
what PC model is this?
when does it happen?  at boot, , or when running
do you have any BSOD ?
can it be overheating?

EFuerte --
If this is something recent, run a System Restore to a time before it started.

I agree with Nobus. Best to start with video driver update.

EFuerte - is the problem solved?
please post some info

Hello

Thank you for your concerns.

After some attempts to solve this "blue screen" Win 7 asked to do a very time consuming operation to try to fix dlls.

After that, Win 7 asked to fix memory problems, I accepted.

And then the problem was solved (until now)

In truth the PC memory cards are a little "rusty" .and had maintenance few days before.

Since the error cause is too much miscellaneous (accordingly with the researchs)
maybe the facts have connection.

>>   Win 7 asked to do a very time consuming operation to try to fix dlls.   <<  i never heard this; this sounds more like someone installing ransomware - post exact message plse

>>  Win 7 asked to fix memory problems  <<  what was the message?