This fix apparently worked for me and one co-worker.
We have HP xw4600 Workstations with pretty high performance specs. 8 GB RAM, 1.2 TB HDD, Quad core 2.5 GHz Intel Core2 CPUs, Windows 7.
For the longest time we would get intermittent BSODs (blue screens of death), either while actively working or while the computer sat idle, with the following error message:
Call your hardware vendor for support
NMI: Parity Check/Memory Parity Error
***The system has halted***
We did days of diagnostics, running the HP system diagnostics over and over again, looking at the Web for information that might help, looking for updated drivers, etc.
In the end, it came down to some conflict my system was having with Forefront Client Security. I replaced it with a copy of AVG Antivirus and now the system seems stable. I let it idle over the weekend to be sure and will keep an eye on it anyhow, but I am hoping, knock on wood, that the system is finally stable.