"PAGE FAULT IN NONPAGED AREA"

Hi there everyone. I've recently run into an error that I've NEVER seen before. It's one of those blue screen of death errors :(. It only started this week and it reads "Page_Fault_In_Nonpaged_Area". It only seems to happen when my computer is sitting idle. It has never happened when I am using the machine, only when it's just sitting there. I've had this system for about 4 years now and never had this problem before. I did put new RAM in during the past year, and I don't know if that could be the problem. I also get a weird error when I close internet explorer sometimes. It's a dialog box that says something like "memory error" and "the memory could not be "read"" "press OK to terminate the program". This error has only come up when I close IE and never any other program. As for the blue screen error, I have no idea what causes it because it only happens when the computer is doing nothing. Weird, eh? This might be a very user-specific problem and I don't expect anyone to have a simple solution to this problem. Could this be bad RAM? I don't suppose it's bad RAM because the fatal error is fairly recent, and the other memory error only happens with the internet explorer program. I'm about to do more tests to see if it is bad RAM, but I think that's unlikely. ANY ADVICE (at all) IS MOST APPRECIATED since this problem seems to be so unique. XD