Question: What is a NMI: Parity Check / Memory Parity Error?

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Question: My IBM “Stinkpad” R60 constantly has a BSOD saying:

*** Hardware Malfucntion
Call your hardware vendor for support
NMI: Parity Check / Memory Parity Error
*** The System has halted ***

I have ran MemTest and Hard disk diagnostics and they come out clean. What’s going on? I have Vista, but the problem is there on XP as well.

Answered by theFakeGeek:

A parity error will usually indicate a memory issue, which you’ve correctly surmised. Now using MemTest you’ve ruled out that there is an issue with the RAM. This is good.

For the benefit of those readers who don’t know what MemTest is I’ll do a quick plug here: MemTest is probably one of the greatest friends a technician can have. MemTest is a software program that randomly reads and writes data to the RAM installed on your computer. If it finds that some of that data is corrupted it notes the sector and classifies the RAM as “bad.” It’s a free program you can download from the MemTest website.

Now back to the problem at hand. Just because your RAM doesn’t have any bad sectors does not mean that we should rule out a memory issue. The first thing that MemTest ignores is any dedicated video memory you might have on your computer (such as a video card.) The parity error might be from that. You can try to rule this out by disabling the video card, if when disabled you no longer get the error then you know where the problem is coming from (hard to do on a laptop however). You might be able to fix it by getting updated drivers.

A second cause of this error could be a problem with the laptop’s power supply (unlikely however.) Memory needs power like every other component in your computer, if that power becomes destabilized or it isn’t receiving enough power problems can occur. The only way to test this is by using a multimeter or swapping in a different power supply (find a different AC adapter.)

Hope that helps ya. If anyone would like to contribute more on the subject just follow the link to the forums.