I just DIY a new PC and experienced the constant BSOD. The BSOD code PFN_LIST_CORRUPT(4E) is almost the same and I never found something else. It's said bad memory could cause this issue,so I used memtest86+ v2.1 to test my memory. It's tested more than 3 hours and no error is found. I also used windiag to test it, but no error is found.Finally, I used windows debug tools to debug the *.dmp files. The following are reports:

The first:
*************************************************************************** ****
* *
* Bugcheck Analysis *
* *
*************************************************************************** ****

PFN_LIST_CORRUPT (4e)
Typically caused by drivers passing bad memory descriptor lists (ie: calling
MmUnlockPages twice with the same list, etc). If a kernel debugger is
available get the stack trace.
Arguments:
Arg1: 0000008f, The free or zeroed page listhead is corrupt
Arg2: 00027784, new page
Arg3: 00007784, old page
Arg4: 00000000, 0

Debugging Details:
------------------


BUGCHECK_STR: 0x4E_8f

PFN_PAGE_SINGLE_BIT_ERROR: Bugcheck args 2 and 3 differ by a bit, its hardware error.

MEMORY_CORRUPTOR: ONE_BIT

CUSTOMER_CRASH_COUNT: 1

DEFAULT_BUCKET_ID: DRIVER_FAULT

PROCESS_NAME: System

IRP_ADDRESS: 8a3ed470

LAST_CONTROL_TRANSFER: from 8051d9e2 to 804faf0d

STACK_TEXT:
ba4c37f8 8051d9e2 0000004e 0000008f 00027784 nt!MmDeleteKernelStack+0x15e
ba4c3840 80697b94 8a3ed4b0 00000000 00000044 nt!IopCompleteRequest+0xde
ba4c3dac 805cfca2 80086000 00000000 00000000 nt!KdpSearchPageHitOffsets+0x994
ba4c3ddc 80546ebe 8069690c 80086000 00000000 nt!`string'+0x2
ba4c3e18 00000000 00000000 00000000 00000000 nt!ExpInsertPoolTracker+0x7b


STACK_COMMAND: kb

FOLLOWUP_NAME: memory_corruption

MODULE_NAME: memory_corruption

IMAGE_NAME: memory_corruption

DEBUG_FLR_IMAGE_TIMESTAMP: 0

FAILURE_BUCKET_ID: MEMORY_CORRUPTION_ONE_BIT

BUCKET_ID: MEMORY_CORRUPTION_ONE_BIT

Followup: memory_corruption
---------------------------------
The second:
*************************************************************************** ****
* *
* Bugcheck Analysis *
* *
*************************************************************************** ****

PFN_LIST_CORRUPT (4e)
Typically caused by drivers passing bad memory descriptor lists (ie: calling
MmUnlockPages twice with the same list, etc). If a kernel debugger is
available get the stack trace.
Arguments:
Arg1: 0000008f, The free or zeroed page listhead is corrupt
Arg2: 0003f604, new page
Arg3: 0001f604, old page
Arg4: 00000000, 0

Debugging Details:
------------------


BUGCHECK_STR: 0x4E_8f

PFN_PAGE_SINGLE_BIT_ERROR: Bugcheck args 2 and 3 differ by a bit, its hardware error.

MEMORY_CORRUPTOR: ONE_BIT

CUSTOMER_CRASH_COUNT: 1

DEFAULT_BUCKET_ID: DRIVER_FAULT

PROCESS_NAME: System

IRP_ADDRESS: 8a3ed470

LAST_CONTROL_TRANSFER: from 8051d9e2 to 804faf0d

STACK_TEXT:
ba4c37f8 8051d9e2 0000004e 0000008f 0003f604 nt!MmDeleteKernelStack+0x15e
ba4c3840 80697b94 8a3ed4b0 00000000 00000044 nt!IopCompleteRequest+0xde
ba4c3dac 805cfca2 80086000 00000000 00000000 nt!KdpSearchPageHitOffsets+0x994
ba4c3ddc 80546ebe 8069690c 80086000 00000000 nt!`string'+0x2
ba4c3e18 00000000 00000000 00000000 00000000 nt!ExpInsertPoolTracker+0x7b


STACK_COMMAND: kb

FOLLOWUP_NAME: memory_corruption

MODULE_NAME: memory_corruption

IMAGE_NAME: memory_corruption

DEBUG_FLR_IMAGE_TIMESTAMP: 0

FAILURE_BUCKET_ID: MEMORY_CORRUPTION_ONE_BIT

BUCKET_ID: MEMORY_CORRUPTION_ONE_BIT

Followup: memory_corruption
---------

CPU: AMD 7750 Black Edition
Moterboard: ASUS M3A78-EM Chipset: 780G/SB700
Memory: CM2X2048-6400C5（1.8v 5-5-5-18）2G
OS: Windows XP Professional SP2

Can anybody help me or give me some advices ? Thx a lot

Update XP to SP3 and also download and install all the many other Windows Updates that you are missing, including all the hardware updates

XP SP3 could really fix my problem? I am not sure about it.I have updated the chipset,VGA, and audio driver, but still BSOD. It's very weired. Most BSOD happened when I surfed online or the computer is booting. When I played game, BSOD never happened. I tested my memory more than 8 hours by memtest+ v2.1 yesterday, and 18 pass no error found...
I dont know how to do now....I am going to replace a new memory module.By the way, I also tested my hard driver by seatools and everything is ok.
Any suggestion?

finally solved this issue. After replacing another memory, everything is ok. Therefore, my BSOD is caused by that memory. It's weired. Though it past memtest86+ test, and no error found, it could not prove your memory is definitely good. If your memory can not pass the memtest86 test, you should be sure your memory is bad.

Thanks for your help!

That error code is a very strong indicator of corrupted memory. As good as Memtest is bad RAM has been known to pass it from time to time but that is the exception and not the rule. Good to see it is resolved.

Now that you have the computer up and running, run Windows Update using the "custom" option and install all the updates you see in the list. Microsoft supplies both Critical and Optional updates. You should always install the critical updates and any hardware updates shown. Because you never installed SP3 you are missing many needed updates