UPDATE:
Leaving the issue with the faulty keyboard aside (wich was taken care of *a while* ago), I managed to update all drivers on the machine, and all seemed fine, but a couple of days after the owner told me the error kept on happening.
It appears that he leaves the computer on pretty much all day, and whe he eventually sits down he finds the computer has obviously rebooted -as in, everything he had open is now closed- and an error dialog that claims windows has recovered from a critical error is there, alone, just floating in the middle of the screen. What does he leave the computer on idle for such long hours wasting electricity? It seems he likes to stream online movies, and then watch them when they are fully loaded -since his internet connection ain't exactly the best-.
Right now, I have the said computer in my power, I've been using it 10 hours straight, streamed 4 movies without problem, ran the most stressfull benchmarks and tests I know SIMULTANEOUSLY and -leaving aside the momentary pseudo freeze the machine logically experienced when all 4 cores were at 100% usage and memory was at 98% (roughly 3.8GB/4GB used of physical RAM and 4GB/4GB cache)- the PC experienced no inestability what so ever, let alone blue screens nor reboots or any Windows failure! After stopping and closing everything the comp went back to normal and I haven't shut it down nor rebooted it ever since.
Now, I know my costumer -who happens to be a friend and a teacher- is not bullshitting me, but I've not only done exactly what he does, but also went as far as push this poor little computer so much I almost felt bad for it, and yet it behaves perfectly. So, I've come down to a theory: whatever it is i'ts causing the BSODs, it HAS to be environmental! Either his building's wire work sucks and there's way too much noise on the line, or his new puppy is licking the USB ports, or a neighbor is testing an homemade EMP bomb without taking proper precautions, or a worker died electrocuted when he was building his apartment; I don't know for sure.. but I'm inclined to think it's something along those lines..
Any further help will be highly appreciated, as well as you having taken the time to read this badly written rant.
PS: excuse if went poetic or dramatic at some point, I'm just in the dire need of some sleep.
