0x9F DRIVER_POWER_STATE_FAILURE on standby; ntoskrnl to blame?

Ever since I installed Service Pack 1 on my Win 7 Pro x64 system, I had an intermittent issue where going into standby sometimes... maybe a quarter of the time? ...it would stay on for ten minutes before shutting off entirely. It wasn't until literally a year later, when I left the monitor on and didn't leave the room, that I managed to catch a BSOD flashing on the screen for a moment just before the computer shut off and realized I might be able to use the code. To make a long story short, I found a tool called NirSoft BlueScreenView, which let me look up the crash data and see that it was an 0x9F DRIVER_POWER_STATE_FAILURE caused by, allegedly, ntoskrnl.exe. Here's the problem — the documentation I've seen on this issue says I need to repair my install from the Windows 7 DVD-ROM to regain a non-corrupted copy of that file. But, if this file was replaced when the Service Pack was installed, doesn't that mean the copy on my disc is outdated?

At any rate, here's a zip file with, I guess, all of the kernel dumps from the BSODs that were still on file as of today and whatever else the Seven Forums utility recorded. Most of the dumps are from crashes related to this issue; the one dated April 3 is probably the only one you need to look at.

Ntoskrnl.exe is not the cause. It is the Kernel which is part of the operating system that manages critical operations and functions.
I've looked through some of your dump files, not all of them as you have a lot which date back quite a while.
One of the issues is caused by your graphics driver being outdated significantly.
Please update it, if you don't know how then here's a useful guide.

http://www.support.amd.com/en-us/kb-...s-install.aspx

Code:

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*                        Bugcheck Analysis                                    *
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Use !analyze -v to get detailed debugging information.

BugCheck 119, {1, 88bd8, 88bda, 88bd9}

Unable to load image \SystemRoot\system32\DRIVERS\atikmpag.sys, Win32 error 0n2
*** WARNING: Unable to verify timestamp for atikmpag.sys
*** ERROR: Module load completed but symbols could not be loaded for atikmpag.sys
Probably caused by : dxgmms1.sys ( dxgmms1!VidSchiVerifyDriverReportedFenceId+ad )

Code:

fffff880`0485d000 fffff880`05357000   atikmdag   (deferred)             
    Image path: \SystemRoot\system32\DRIVERS\atikmdag.sys
    Image name: atikmdag.sys
    Timestamp:        Fri Apr 06 02:48:25 2012 (4F7E4B69)
    CheckSum:         00AABC48
    ImageSize:        00AFA000
    Translations:     0000.04b0 0000.04e4 0409.04b0 0409.04e4

If you are still getting issues then please enable driver verifier as another driver is probably at fault.
Follow these instructions on how to enable Driver Verifier.

Driver Verifier - Enable and Disable

Zip up the dump files found in C:/Windows/Minidump and upload them in your next reply.

Ouch. I remember having the impression that the crashes were caused by my video driver, but couldn't remember exactly what told me that. Last week I went through a lot of rigmarole wiping the one I had and installing the latest one (Catalyst 13.9), but as you can see, that hasn't stopped the crashes from happening. All I need to know is what went wrong on April 3; that's after I had installed the new driver. If it's still the driver, is it possible that the issue is with the card itself?

You can try running Furmark to see if the GPU is failing. Follow these instructions.

Video Card - Stress Test with Furmark

Well, nothing went wrong (I didn't realize I was supposed to stop it manually so I ended up letting it run until the bar reached the right side of the screen and started scrolling), but that didn't particularly surprise me. So should I contact AMD about the driver, you think? I don't know what else I can do if a newly-installed driver is failing so consistently.

Right, can you try updating your driver to the latest version, if it is the latest version can you please roll back to an earlier version.
Here's some instructions on how to do it.

How-To Install AMD Catalyst? Drivers For A Windows® Based System

I know you said you've done this in the past but I'd like you to do it again.