STOP: C000021A {Fatal System Error} Win7 x64


  • Initially, while trying to install Win7 x64 on a Toshiba laptop I get the BSOD error "STOP: c000021a {Fatal System Error}"  After a couple of retries / hard drive juggling I managed to get it working, and install successfully.

    I played around with it for a while, installed drivers, rebooted, etc, everything was fine. However, once I shut the system down, and went to use it an hour or so later, Windows will now no longer start.  It goes to the point of "Starting Windows" with the swirly logo thing, then crashes, with the same STOP error it gave when trying to install. "STOP: c000021a {Fatal System Error}"

    I have managed to get it to start in Safe Mode once, but that wasn't much help, and now it won't start in any mode.  The Repair Console is no help either, it sits there for half an hour, then tells me that something is wrong, but it couldn't fix it.

    I know its not the ISO I downloaded either, because I used the same disc on another machine just fine.

    Laptop is a Toshiba L300D-PSLC8C
    AMD Athlon X2 2.00Ghz
    ATi Radeon 3100
    2GB RAM
    250GB HDD

    From what I'm finding in other places on the net, this is a frequent issue for Toshiba owners and Win7 x64.
    Wednesday, July 29, 2009 2:48 PM


  • Argh.  I fixed it again. Same as the issue I had on my Desktop machine only a few hours earlier.  Turning off Dynamic CPU speed (Cool 'n Quiet / SpeedStep, etc) fixed this issue as well.  There's something seriously wrong with Win7 x64 and AMD Power Managment it seems.
    • Marked as answer by ArchonTiger Wednesday, July 29, 2009 4:09 PM
    Wednesday, July 29, 2009 4:08 PM