Typical behaviour from a machine without the EDAC modules loaded is to:
Ignore PCI parity errors (some may trigger an NMI on some types of parity error).
Ignore correctable RAM errors entirely.
(Maybe) trigger an NMI on the first uncorrectable RAM error (this will probably get you this error in the kernel logs: "Uhhuh. NMI received. Dazed and confused, but trying to continue. You probably have a hardware problem with your RAM chips").