Because RAM is used to buffer writes to the hard disk, any app, OS or data on the hard drive can be corrupt now.
It's a shame not much is told about the machine. It could be the old PC that the owner didn't know about canned air, cleaning and more.
Bob
Basically, I was playing minecraft one day (Windows had installed some updates the night before, IIRC), my computer shuts down out of nowhere, about 5 minutes into me playing. Now, when I reboot and attempt to log in (Windows Vista), it acts like I logged in successfully, but then the screen goes black, no mouse, pointer, etc and the computer basically shuts off or reboots. I said screw it, and installed Windows 7 from scratch on a fresh partition, that does the same thing (Go to log in and it shuts down after logging in). Both versions of Windows will boot up and allow me to log in via safe mode, which is where I tested my RAM, which came up with a few errors, so I replaced the RAM. Just installed it ten minutes ago and tried again, still getting this error. Any ideas? All my drivers appear to be fine, so unless it's a failing piece of hardware that isn't used in safe mode, I'm pretty much stumped.

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