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I am receiving a run-time parity error during operation of the PC, after booting

Explanation: A parity error is occurring on the PC as it is being used. The parity error may occur consistently or intermittently. It is also normal to see parity errors in Windows but not in DOS because Windows exercises the memory much more than DOS does.

Diagnosis: Parity errors are often a signal that something is working incorrectly in the system. This is commonly a problem with the memory itself, but can be caused by many other sorts of hardware problems as well. You may be surprised at some of the hardware problems that can lead to memory corruption, including expansion card issues, resource conflicts, etc. This is why parity checking is so important.

Recommendation: Look on the screen to see if the system is giving you any sort of memory address that indicates where the parity error is occurring. Reboot the system and see if the same address comes up again, and then reboot a third time. Take note of whether or not the memory location changes, and then continue below:

• You may be surprised to hear me say this, but if your system has been working well for a long time, you haven't changed anything recently, and you only encountered a single parity error, I often recommend just ignoring it. Well, don't ignore it, but don't take any action other than seeing if it happens again, and if so, under what circumstances. The reason is that fluke corruptions of memory occur, sometimes due to stray radiation or odd power glitches. You may have a single error and never another one. If the error recurs, of course, you have a problem that needs to be addressed.
• Check for resource conflicts, particularly if you have just added any hardware to the system.
• You could have a real problem with your memory. Diagnose the memory itself here.
• There are many different possible causes of intermittent system lockups and glitches. Many of the problems that manifest themselves as lockups, crashes or spontaneous reboots on a non-parity system will show up on a parity system as parity errors.

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