Client's HP Pavilion M9400t was reported as having a noisy fan and then would not boot any longer. The power supply was the primary reason for the system not powering but after replacing the power supply the system would continually reboot. Using the F8 key while booting we were able to force the system to stop on the error and not reboot. This allowed the error message STOP 0x0000007B to be displayed. This error most often is reported when there is a hardware issue.
After backing up the hard drive using Norton Ghost, we went through a series of tests by removing hardware. In this case the video card was an add-in so it was removed but the problem still persisted. Next we checked the BIOS settings and noted the default for the SATA drive was set to RAID. We changed this to IDE and rebooted the system. The system booted normally.
How To Change the BIOS Setting
With many HP systems you can change the BIOS as follows.
After making this change, your computer should reboot. You should check your Windows Updates to see if there were recent updates that might have contributed to boot failure and the hard drive configuration. If so, you might want to consider rolling back this update or finding a driver direct from HP.
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