- 1). Disconnect the computer and open the case. Remove all memory sticks from the motherboard. Use compressed air to clean away any dust or other particles from inside the case. Pay special attention to removing any dust from the RAM slots and from the sticks themselves. If any particles have worked their way down into the slot they can disrupt the connection and possible cause parity errors. Cleaning inside the computer and the RAM slots, may fix the problem without having to resort to replacing components. Once all the particles have been removed from inside the case, reinstall the RAM and see if the error returns.
- 2). Remove the sticks and check that they are able to run at the same speeds. Parity errors can occur when there is a disparity between memory speeds. For instance, if one stick is a PC2700, the other sticks must also be compatible with PC2700. Parity errors due to incompatible memory sticks typically will only occur when memory is installed for the first time. If a computer has had the same memory installed for a while but only recently began to display parity errors, incompatibility is unlikely to be the problem.
- 3). Download and run a memory tester such as memtest86+. Memory testers can tell if there is a physical problem with the memory, indicating the component is bad. Look for a memory tester that is able to perform extended stress tests, as some parity errors occur when the speed of one of the sticks begins to diminish after being in use for awhile.
- 4). Install each memory stick individually. With one stick installed in the computer, start the machine and run the memory tester. Memory testers are unable to differentiate between individual sticks of RAM installed in a computer. Even if memory fails a test, not all sticks are necessarily bad. By testing each stick individually you can pinpoint the bad component. Replace any memory sticks that test as bad, ensuring that the new sticks are fully compatible with those already installed in a machine.
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