BSOD Crashes Windows 7

[Adon]

My computer since some time instantly crashes with similar reports. It does during normal using (browsing websites, listening to music etc.).

Last three crashes reported:

BCCode: 7f
BCP1: 0000000000000008
BCP2: 0000000080050031
BCP3: 00000000000006F8
BCP4: FFFFF800028567A0

BCCode: 7f
BCP1: 0000000000000008
BCP2: 0000000080050031
BCP3: 00000000000006F8
BCP4: FFFFF8000288F3F0

BCCode: 7f
BCP1: 0000000000000008
BCP2: 0000000080050031
BCP3: 00000000000006F8
BCP4: FFFFF8000287D85F

It hapens randomely, sometimes few times a day, sometimes once a day.
The machine worked fine under WinXP, the under Win7RC, and on the beginning with Win7 x64 Ultimate. Now it's a clean install and it crahes anyway.
First thought that came to my mind is the RAM problem, but I tested it with memtest, IntalBurnTest (with extreme profile) and BurnInTest Pro and everything is fine. System isn't overclocked (even RAM run over spec as 533MHz). Does anybody have an idea what can cause a problem?
I'm attaching last 2 dumps.
My PC specification is:
Win7 x64 Ultimate
Intel Core i7 920
Gigabyte GA-EX58-UD3R Intel X58 rev. 1.6
Patriot Viper 6GB (3x2GB) DDR3 PC3-12800
Palit GeForce GTS 250 Green 1024MB GDDR3
Sound Blaster Audigy SE
Tagan TG580-U15 580W ATX2.01
Zalman CNPS9500A-LED CPU Cooler

Thanks in advance.

 

[Crispy]

STACK_COMMAND: kb

FOLLOWUP_IP:
NETIO!CompareSecurityContexts+6a
fffff880`01406c5a 448b442470 mov r8d,dword ptr [rsp+70h]

SYMBOL_STACK_INDEX: 6

SYMBOL_NAME: NETIO!CompareSecurityContexts+6a

FOLLOWUP_NAME: MachineOwner

MODULE_NAME: NETIO

IMAGE_NAME: NETIO.SYS

DEBUG_FLR_IMAGE_TIMESTAMP: 4a5bc18a

FAILURE_BUCKET_ID: X64_0x7f_8_NETIO!CompareSecurityContexts+6a

BUCKET_ID: X64_0x7f_8_NETIO!CompareSecurityContexts+6a

Followup: MachineOwner

Try setting your IP address manually,

[FONT=Consolas, monospace][FONT=Verdana, sans-serif]1. On the client computer, click Control Panel, then click Network and Sharing Center.[/FONT][/FONT]​

[FONT=Consolas, monospace][FONT=Verdana, sans-serif]2. Right-click Local Area Connection and click Status.[/FONT][/FONT]​

[FONT=Consolas, monospace][FONT=Verdana, sans-serif]3. Click Properties.[/FONT][/FONT]​

[FONT=Consolas, monospace][FONT=Verdana, sans-serif]4. Click Internet Protocol Version 4 (ICP/IPv4) or Internet Protocol Version 6 (ICP/IPv6) and then click Properties.[/FONT][/FONT]​

[FONT=Consolas, monospace][FONT=Verdana, sans-serif]5. Select Use the following IP address and enter the values in IP address, Subnet mask, Default gateway, and Preferred DNS server.[/FONT][/FONT]​

[FONT=Consolas, monospace][FONT=Verdana, sans-serif]6. Click OK.[/FONT][/FONT]​