Win 7 professional crashes randomly on older PC

Hi people.
As many other users of win 7 I experience one quite common problem, that is my desktop PC crashes randomly, sometimes few times a day and sometimes every 1-2 days, automatically rebooting and showing the famous BSOD.

But as I already tried so many things to troubleshoot the problem, and couldn't solve it after all, I'm starting this thread seeking for some new suggestions and tips.

I'll describe in details my PC configuration and all things that I already tried in order to fix the issue:

Motherboard: Gigabyte 8L848P-G
CPU: Prescott, Pentium 4 HT, 3GHZ, 1mb L2 cashe
RAM: 2x512MB, both DDR1-400, PC3200, Kingmax and Kingston
GPU: GeForce MX440, nVidia NV17, 64mb
HDD: SATA Seagate, 160 gb and SATA2 Samsung 7200, 1tb
OS: MultiOS, Windows XP SP3 + Windows 7 professional
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OK. As I said, my PC is randomly reboots and displays BSOD.
I used WhoCrashed utility to analyze minidump files and I'll paste codes from last few crashes:

Code:

On Sat 1.1.2011 23:23:14 GMT your computer crashed
crash dump file: C:\Windows\Minidump\010211-16921-01.dmp
This was probably caused by the following module: aswfsblk.sys (aswFsBlk+0x15B4) 
Bugcheck code: 0x19 (0x3, 0xFFFFFFFF8462F900, 0xFFFFFFFF8462F900, 0x810600)
Error: BAD_POOL_HEADER
file path: C:\Windows\system32\drivers\aswfsblk.sys
product: avast! Antivirus System
company: AVAST Software
description: avast! File System Access Blocking Driver
Bug check description: This indicates that a pool header is corrupt.
This appears to be a typical software driver bug and is not likely to be caused by a hardware problem. This might be a case of memory corruption. More often memory corruption happens because of software errors in buggy drivers, not because of faulty RAM modules. 
A third party driver was identified as the probable root cause of this system error. It is suggested you look for an update for the following driver: aswfsblk.sys (avast! File System Access Blocking Driver, AVAST Software). 
Google query: aswfsblk.sys AVAST Software BAD_POOL_HEADER




On Fri 31.12.2010 21:28:52 GMT your computer crashed
crash dump file: C:\Windows\Minidump\123110-14671-01.dmp
This was probably caused by the following module: ntoskrnl.exe (nt+0x206060) 
Bugcheck code: 0x10000050 (0xFFFFFFFFFA7585A5, 0x1, 0xFFFFFFFF82A0C060, 0x2)
Error: CUSTOM_ERROR
file path: C:\Windows\system32\ntoskrnl.exe
product: Microsoft® Windows® Operating System
company: Microsoft Corporation
description: NT Kernel & System
The crash took place in the Windows kernel. Possibly this problem is caused by another driver which cannot be identified at this time. 


On Thu 30.12.2010 0:54:52 GMT your computer crashed
crash dump file: C:\Windows\Minidump\123010-16328-01.dmp
This was probably caused by the following module: win32k.sys (win32k+0xCCDB6) 
Bugcheck code: 0x1000008E (0xFFFFFFFFC000001D, 0xFFFFFFFF91D5CDB6, 0xFFFFFFFF9F894C18, 0x0)
Error: KERNEL_MODE_EXCEPTION_NOT_HANDLED_M
file path: C:\Windows\system32\win32k.sys
product: Microsoft® Windows® Operating System
company: Microsoft Corporation
description: Multi-User Win32 Driver
Bug check description: This indicates that a kernel-mode program generated an exception which the error handler did not catch.
This appears to be a typical software driver bug and is not likely to be caused by a hardware problem. 
The crash took place in a standard Microsoft module. Your system configuration may be incorrect. Possibly this problem is caused by another driver on your system which cannot be identified at this time. 


On Wed 29.12.2010 8:34:23 GMT your computer crashed
crash dump file: C:\Windows\Minidump\122910-15046-01.dmp
This was probably caused by the following module: aswsp.sys (aswSP+0x15B01) 
Bugcheck code: 0x100000BE (0xFFFFFFFF97795000, 0x3BCA2802, 0xFFFFFFFF9A566AC4, 0xE)
Error: CUSTOM_ERROR
file path: C:\Windows\system32\drivers\aswsp.sys
product: avast! Antivirus System
company: AVAST Software
description: avast! self protection module
A third party driver was identified as the probable root cause of this system error. It is suggested you look for an update for the following driver: aswsp.sys (avast! self protection module, AVAST Software). 
Google query: aswsp.sys AVAST Software CUSTOM_ERROR




On Tue 28.12.2010 20:46:14 GMT your computer crashed
crash dump file: C:\Windows\Minidump\122810-14765-01.dmp
This was probably caused by the following module: ntoskrnl.exe (nt+0x206064) 
Bugcheck code: 0x10000050 (0xFFFFFFFFFFE4E112, 0x0, 0xFFFFFFFF82A0E064, 0x0)
Error: CUSTOM_ERROR
file path: C:\Windows\system32\ntoskrnl.exe
product: Microsoft® Windows® Operating System
company: Microsoft Corporation
description: NT Kernel & System
The crash took place in the Windows kernel. Possibly this problem is caused by another driver which cannot be identified at this time. 


On Tue 28.12.2010 19:11:27 GMT your computer crashed
crash dump file: C:\Windows\Minidump\122810-17031-01.dmp
This was probably caused by the following module: ntoskrnl.exe (nt+0x3579A) 
Bugcheck code: 0x10000050 (0xFFFFFFFFF5B5DC6C, 0x0, 0xFFFFFFFFF5B5DC6C, 0x2)
Error: CUSTOM_ERROR
file path: C:\Windows\system32\ntoskrnl.exe
product: Microsoft® Windows® Operating System
company: Microsoft Corporation
description: NT Kernel & System
The crash took place in the Windows kernel. Possibly this problem is caused by another driver which cannot be identified at this time. 


On Tue 28.12.2010 14:43:47 GMT your computer crashed
crash dump file: C:\Windows\Minidump\122810-16093-01.dmp
This was probably caused by the following module: ntoskrnl.exe (nt+0x206057) 
Bugcheck code: 0x1000008E (0xFFFFFFFFC0000005, 0xFFFFFFFF82A0C057, 0xFFFFFFFF9A353C58, 0x0)
Error: KERNEL_MODE_EXCEPTION_NOT_HANDLED_M
file path: C:\Windows\system32\ntoskrnl.exe
product: Microsoft® Windows® Operating System
company: Microsoft Corporation
description: NT Kernel & System
Bug check description: This indicates that a kernel-mode program generated an exception which the error handler did not catch.
This appears to be a typical software driver bug and is not likely to be caused by a hardware problem. 
The crash took place in the Windows kernel. Possibly this problem is caused by another driver which cannot be identified at this time. 


On Mon 27.12.2010 22:13:09 GMT your computer crashed
crash dump file: C:\Windows\Minidump\122710-15171-01.dmp
This was probably caused by the following module: ntoskrnl.exe (nt+0x206057) 
Bugcheck code: 0x1000008E (0xFFFFFFFFC0000005, 0xFFFFFFFF82A50057, 0xFFFFFFFF8C658C58, 0x0)
Error: KERNEL_MODE_EXCEPTION_NOT_HANDLED_M
file path: C:\Windows\system32\ntoskrnl.exe
product: Microsoft® Windows® Operating System
company: Microsoft Corporation
description: NT Kernel & System
Bug check description: This indicates that a kernel-mode program generated an exception which the error handler did not catch.
This appears to be a typical software driver bug and is not likely to be caused by a hardware problem. 
The crash took place in the Windows kernel. Possibly this problem is caused by another driver which cannot be identified at this time. 


On Mon 27.12.2010 21:37:04 GMT your computer crashed
crash dump file: C:\Windows\Minidump\122710-16609-01.dmp
This was probably caused by the following module: ntoskrnl.exe (nt+0x206057) 
Bugcheck code: 0x1000008E (0xFFFFFFFFC0000005, 0xFFFFFFFF82A1E057, 0xFFFFFFFF96833C58, 0x0)
Error: KERNEL_MODE_EXCEPTION_NOT_HANDLED_M
file path: C:\Windows\system32\ntoskrnl.exe
product: Microsoft® Windows® Operating System
company: Microsoft Corporation
description: NT Kernel & System
Bug check description: This indicates that a kernel-mode program generated an exception which the error handler did not catch.
This appears to be a typical software driver bug and is not likely to be caused by a hardware problem. 
The crash took place in the Windows kernel. Possibly this problem is caused by another driver which cannot be identified at this time.

I tested both memory sticks individually and together in mem86+ utility and all tests went without memory problems. I reinstalled driver of the video card because I read that this types of STOP msg can be invoked by incompatible video driver. I used newest version and then older versions of the driver but crashes continued. Also I read somewhere on the web that AV software can cause this BSODs to happen. I have Avast free AV installed, but same version I have on another, newer PC and it works fine. It also has win 7 OS and Avast free AV, so I excluded AV as possible cause reason for the BSODs. I went through Win 7 driver update feature and all drivers seems to be newest versions... Also BIOS version is F5 and that is according to the manufacturer site newest version of the BIOS for this mobo.

Any suggestions?

P.S. If someone needs more info Ill provide them asap.
Ty, Dean

Anybody!?

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Any solution?

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