Problem:You try to boot into windows and it blue screens on you. Being a clever fellow you try safe mode and everything seems to be going great until the computer seemingly freezes when loading something called agp400.sys
Fix: Disable the video card driver using the Windows XP Recovery Console.
This problem is caused by an incompatible video card driver that has been recently installed. What you need to do is disable the driver so that windows can boot normally. Once the computer is in windows and the desktop loads download a “known good” version of the driver. You might also want to update the BIOS (flash it.)
THE METHOD:
- You need to load into recovery console using your Windows XP OS Disc. I’ll assume you know how to do this. (If you don’t it’s really easy, just ask me on the forums and I’ll be glad to outline the steps.)
- Making sure you’re logged into the proper windows installation, type in “listsvc“. This will pull up a listing of all the current services and drivers on your computer.
- Type in “Disable” and then the driver that you want to disable. In this case it will be the agp400.sys driver.
- Reboot into Windows.
- Find a “known good” version of the driver. Perhaps even an older one.
- <OPTIONAL> Some of these incompatibilities are solved with a new BIOS revision. You could try flashing the BIOS using a new revision from the manufacturers site and then reinstalling the video card driver. Could solve things.
ALTERNATE METHOD:
If the above does not work you might need to fix some errors first. Run a disk check using recovery console.
- You need to load into recovery console using your Windows XP OS Disc. I’ll assume you know how to do this. (If you don’t it’s really easy, just ask me on the forums and I’ll be glad to outline the steps.)
- Making sure you’re logged into the proper windows installation, type in “chkdsk /r.” This will force windows to do a thorough disk check and fix any errors it finds.
- After it is done try booting into windows. If the problem persists apply the first method.
Good luck!
How to explain this problem to the client: After installing a new version of a video driver that was incompatible with your system (perhaps from Windows Update) the computer crashed whenever it tried to load that driver. We’ve removed the bad driver and installed a known good one. Your computer works great!
Good luck and tell me how it goes on the forums.