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I'm experiencing a BSOD. The issue is an unhandled thread exception in atikmdag.sys. That's part of my ATI video drivers.

I can consistently reproduce the issue by switching users or by connecting to the machine with remote desktop (which is, of course, switching users).

I've unplugged most of my peripherals for the sake of debugging this. That leaves me with:

  • Core i5 750
  • 8 gb ram
  • Big beefy hard drive with 25% free
  • 64-bit windows 7 ultimate
  • ATI Radeon HD 5700, latest drivers
  • Windows is up to date
  • High end 850 watt power supply with beefy rails

I've done a basic sanity check, including testing memory with memtest86+ and testing my HDD with the drive manufacturer's utility.

Googling revealed a lot of different stuff, but most of it pointed to fairly obscure things. Some of it was related to borked hardware setups, like not having a strong enough power supply.

When I originally built this system a year and a half ago, I bought a high quality 650 watt power supply with beefy rails. I've added quite a few peripherals and 2 hard drives since then, so I thought maybe I was under powering the system, although my current calculations suggest I should be ok. I went ahead and upgraded to the 850 watt I list above just to be sure. The issue did not change with that.

What would you suggest as a next step? Do you think there is any chance I actually fried the video card over time by not having enough juice going to it?

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up vote 0 down vote accepted

I did not find the solution to this issue, but it apparently was a software level cause. After upgrading to Windows 8 a couple days after posting this, I am no longer experienced this issue or anything like it.

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