This is my tip, if your Windows XP suddenly starts to crash with "Blue Screen of Death", (possibly) with error "IRQL_NOT_LESS_OR_EQUAL".

If it starts to crash, remember what programs you have installed just before crashes started to occur. I personally have noticed, that my XP system doesn't seem to like some system driver (.sys) files. So if you have installed programs, that installs those .sys files to your system and your computer starts to crash after that, try to UNinstall those apps to see if that helps.

You can also stop .sys files from being loaded to memory at Windows start up, using AutoRuns program. Just go to 'Drivers' tab and uncheck wanted driver file.

System driver files are usually installed to Windows/system32/drivers folder. In some cases they are installed to program own folder (Program Files/<program>).

This is just one possible reason that might cause crashing, based to my own experiences. There are also MANY other reasons.

I think it could be a memory thing

I was under the assumption correct or incorrect that:
If duplicated .dll files were in program files folders, and in the Windows\System32 folder that the Windows\System32 folder would contain the .dll file that would be used by the OS instead of any duplicated .dll files installed by programs into their very own unique program files folders.

What makes this assumption even more confusing is I've noticed in the past when an updated .dll is installed into the Windows\System32 folder that sometimes something is done in the registry for programs that have their own version installed.

Andavari: Don't quite understand what are you talking about. I'm talking about .sys files, not .dll files. Did you perhaps misunderstood the line that you quote?