drivers_irql_not_less_than_or_equal

Hey!
I've searched the wild internet for a diagnosis and an appropriate solution, but there's such a wide variety that I seek a definitive answer. My computer BSODs every time I boot with networking enabled. I tried updating my network adapter drivers, which seems to have provided a momentary fix, though I'm unsure if this is the true problem at work here.

I run windows 7 home premium 64-bit on an Acer aspire 5517. I bought the computer from a friend of mine and its other specifications are therefore unknown to me.

Thank you for your time.

Welcome to SF.

*** WARNING: Unable to verify timestamp for athrx.sys
*** ERROR: Module load completed but symbols could not be loaded for athrx.sys
Probably caused by : athrx.sys ( athrx+2edf7 )

Click to expand...

ATI Video driver is old:
Driver c:\windows\system32\drivers\atikmdag.sys (8.1.1.921, 5.76 MB (6,038,016 bytes), 8/15/2009 4:15 PM)

Atheros network driver is old:
Driver c:\windows\system32\drivers\athrx.sys (8.0.0.177, 1.42 MB (1,488,384 bytes), 8/15/2009 4:15 PM)

Realtec audio driver is old.

Please update all three drivers.

sptd.sys

Please remove any CD virtualization programs such as Daemon Tools and Alcohol 120%. They use a driver, found in your dmp, sptd.sys, that is notorious for causing BSODs. Use this SPTD uninstaller when you're done:
http://www.duplexsecure.com/en/downloads

thanks!