Bluescreen randomly "irql_not_less_or_equal"?!?

Welcome aboard.

Well, the cause of your problem is ..... McAfee

Code:

fffff880`0355a608  fffff880`05f31aaeUnable to load image \SystemRoot\system32\drivers\mfefirek.sys, Win32 error 0n2
*** WARNING: Unable to verify timestamp for mfefirek.sys
*** ERROR: Module load completed but symbols could not be loaded for mfefirek.sys
 mfefirek+0x28aae

And again McAfee

Code:

fffff880`0355b218  fffff880`01acac9a tcpip! ?? ::FNODOBFM::`string'+0x50b52
fffff880`0355b220  fffff880`047e2100Unable to load image \SystemRoot\system32\DRIVERS\mfenlfk.sys, Win32 error 0n2
*** WARNING: Unable to verify timestamp for mfenlfk.sys
*** ERROR: Module load completed but symbols could not be loaded for mfenlfk.sys
 mfenlfk+0xb100

Gate rid of Mcafee, as early as possible.
Use Microsoft Security Essentials - Microsoft Windows.

Then you have one mote thing to do ..... upgrade the network driver:

Download the network card driver from manufactuer's website, Realtek
Then reinstall the driver:

1. Click the Start Button, type "devmgmt.msc" (without quotation marks) in the Start Menu Search box and press Enter.
2. Double click to expand "Network adaptors".
3. Right click your network card and click Uninstall.
4. Check "Delete driver software for this device" check box, click OK.
5. Restart the computer
6. If windows does not auto configure the appropriate drivers at startup, install the downloaded one manually.

Because it is somehow old

Code:

lmvm Rt64win7
start             end                 module name
fffff880`04c69000 fffff880`04ced000   Rt64win7 T (no symbols)           
    Loaded symbol image file: Rt64win7.sys
    Image path: \SystemRoot\system32\DRIVERS\Rt64win7.sys
    Image name: Rt64win7.sys
    Timestamp:        Mon May 16 20:23:31 2011 (4DD13A6B)
    CheckSum:         000859EC
    ImageSize:        00084000
    Translations:     0000.04b0 0000.04e4 0409.04b0 0409.04e4

And it is failing there, too.

Code:

fffff880`0355adf8  fffff880`04c84298Unable to load image \SystemRoot\system32\DRIVERS\Rt64win7.sys, Win32 error 0n2
*** WARNING: Unable to verify timestamp for Rt64win7.sys
*** ERROR: Module load completed but symbols could not be loaded for Rt64win7.sys
 Rt64win7+0x1b298

Let us know when you are done.

Wait, and see. Best of luck :)

You are welcome :)

And nothing to owe