ntoskrnl.exe windows 7 64bit

Your crash dumps are not showing any finite probable cause.

Seatool for dos: SeaTools | Seagate download. Burn it in a blank cd. boot from the CD, click on "Accept", wait for it to finish detecting the drives, then in the upper left corner select "Basic Tests", then select "Long Test" and let it run.

Test your RAM modules for possible errors.
How to Test and Diagnose RAM Issues with Memtest86+
Run memtest for at least 8 passes, preferably overnight.

If both of those tests come clean, enable Driver Verifier to monitor the drivers.
Driver Verifier - Enable and Disable
Run Driver Verifier for 24 hours or the occurrence of the next crash, whichever is earlier.

   Information

Why Driver Verifier:
It puts a stress on the drivers, ans so it makes the unstable drivers crash. Hopefully the driver that crashes is recorded in the memory dump.

How Can we know that DV is enabled:
It will make the system bit of slow, laggy.

   Warning

Before enabling DV, make it sure that you have earlier System restore points made in your computer. You can check it easily by using CCleaner looking at Tools > System Restore.

If there is no points, make a System Restore Point manually before enabling DV.

   Tip

• If you fail to get on the Desktop because of DV, Boot into Advanced Boot Options > Safe mode. Disable DV there. Now boot normally again, and try following the instruction of enabling DV again.
• If you cannot boot in Safe mode too, do a System Restore to a point you made earlier.

Let us know the results, with the subsequent crash dumps, if any. Post it following the Blue Screen of Death (BSOD) Posting Instructions.
_____________________________________________________________________________
BSOD ANALYSIS:

Code:

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*                        Bugcheck Analysis                                    *
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Use !analyze -v to get detailed debugging information.

BugCheck A, {a8f223, 2, 0, fffff800030d45c7}

Probably caused by : ntkrnlmp.exe ( nt!IoBoostThreadIoPriority+1e7 )

Followup: MachineOwner
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2: kd> !analyze -v
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*                        Bugcheck Analysis                                    *
*                                                                             *
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IRQL_NOT_LESS_OR_EQUAL (a)
An attempt was made to access a pageable (or completely invalid) address at an
interrupt request level (IRQL) that is too high.  This is usually
caused by drivers using improper addresses.
If a kernel debugger is available get the stack backtrace.
Arguments:
Arg1: 0000000000a8f223, memory referenced
Arg2: 0000000000000002, IRQL
Arg3: 0000000000000000, bitfield :
    bit 0 : value 0 = read operation, 1 = write operation
    bit 3 : value 0 = not an execute operation, 1 = execute operation (only on chips which support this level of status)
Arg4: fffff800030d45c7, address which referenced memory

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


READ_ADDRESS: GetPointerFromAddress: unable to read from fffff800032c3100
GetUlongFromAddress: unable to read from fffff800032c31c0
 0000000000a8f223 Nonpaged pool

CURRENT_IRQL:  2

FAULTING_IP: 
nt!IoBoostThreadIoPriority+1e7
fffff800`030d45c7 418a442422      mov     al,byte ptr [r12+22h]

CUSTOMER_CRASH_COUNT:  1

DEFAULT_BUCKET_ID:  WIN7_DRIVER_FAULT

BUGCHECK_STR:  0xA

PROCESS_NAME:  UserAccountCon

TRAP_FRAME:  fffff880088b7830 -- (.trap 0xfffff880088b7830)
NOTE: The trap frame does not contain all registers.
Some register values may be zeroed or incorrect.
rax=fffff880088b7a40 rbx=0000000000000000 rcx=fffff880088b7a58
rdx=fffffa80075f0d7e rsi=0000000000000000 rdi=0000000000000000
rip=fffff800030d45c7 rsp=fffff880088b79c0 rbp=0000000000000000
 r8=0000000000000000  r9=0000000000000000 r10=0000000000000000
r11=0000000000000001 r12=0000000000000000 r13=0000000000000000
r14=0000000000000000 r15=0000000000000000
iopl=0         nv up ei pl nz na po cy
nt!IoBoostThreadIoPriority+0x1e7:
fffff800`030d45c7 418a442422      mov     al,byte ptr [r12+22h] ds:00000000`00000022=??
Resetting default scope

LAST_CONTROL_TRANSFER:  from fffff8000308b1a9 to fffff8000308bc00

STACK_TEXT:  
fffff880`088b76e8 fffff800`0308b1a9 : 00000000`0000000a 00000000`00a8f223 00000000`00000002 00000000`00000000 : nt!KeBugCheckEx
fffff880`088b76f0 fffff800`03089e20 : 00000000`00000000 fffff800`030981f8 00000000`00000000 00000000`00000001 : nt!KiBugCheckDispatch+0x69
fffff880`088b7830 fffff800`030d45c7 : fffff880`088b7d80 00000000`007092e0 00000000`00000001 fffff800`03094a43 : nt!KiPageFault+0x260
fffff880`088b79c0 fffff800`0306ba65 : fffffa80`07443b60 00000000`00000002 fffffa80`07443f50 fffff880`088b7a40 : nt!IoBoostThreadIoPriority+0x1e7
fffff880`088b7b70 fffff800`0306bb1d : fffffa80`06ae8050 00000000`00000001 00000000`00000000 fffff880`02f42180 : nt!ExpCheckForIoPriorityBoost+0x151
fffff880`088b7bb0 fffff800`03090dac : ffffffff`ffb3b4c0 fffffa80`08835460 fffffa80`06ae8050 00000000`fffffff8 : nt!ExpWaitForResource+0x8d
fffff880`088b7c20 fffff880`0125a29a : 00000000`c00000d8 00000000`00000001 00000000`00000000 fffff960`000bef84 : nt!ExAcquireResourceExclusiveLite+0x14f
fffff880`088b7c90 fffff880`012f4bd3 : fffffa80`06824830 fffff8a0`07a82010 fffff8a0`01c6426a fffff900`c0582401 : Ntfs!NtfsAcquireFcbWithPaging+0x13a
fffff880`088b7cf0 fffff880`012f2dc2 : fffffa80`06824830 fffffa80`077d2350 fffff8a0`002a91d0 fffff960`000fd401 : Ntfs!NtfsFindPrefixHashEntry+0xabe
fffff880`088b7e20 fffff880`012f0701 : fffffa80`06824830 fffffa80`06a502a0 fffff880`088b7ff0 fffff880`088b8040 : Ntfs!NtfsFindStartingNode+0x452
fffff880`088b7ef0 fffff880`0125a40d : fffffa80`06824830 fffffa80`06a502a0 fffff880`088b82a0 fffff880`088b8500 : Ntfs!NtfsCommonCreate+0x3e1
fffff880`088b80d0 fffff800`03097878 : fffff880`088b8210 00000000`00000000 fffff880`77ce4bda fffff880`088b83d0 : Ntfs!NtfsCommonCreateCallout+0x1d
fffff880`088b8100 fffff880`0125ab8f : fffff880`0125a3f0 fffff880`01259a20 fffff880`088b8200 fffff880`012fad00 : nt!KeExpandKernelStackAndCalloutEx+0xd8
fffff880`088b81e0 fffff880`012f378c : 00000000`00000000 00000000`00000000 fffff880`088b8440 fffffa80`06a502a0 : Ntfs!NtfsCommonCreateOnNewStack+0x4f
fffff880`088b8240 fffff880`00e02bcf : fffffa80`077d1030 fffffa80`06a502a0 00000000`00000000 00000000`00000000 : Ntfs!NtfsFsdCreate+0x1ac
fffff880`088b83f0 fffff880`00e222b9 : fffffa80`06a502a0 fffffa80`0780a010 fffffa80`06a50200 fffffa80`076a7de0 : fltmgr!FltpLegacyProcessingAfterPreCallbacksCompleted+0x24f
fffff880`088b8480 fffff800`0338cfdc : 00000000`00000045 fffffa80`079bacc8 fffffa80`06f9e440 00000000`00000000 : fltmgr!FltpCreate+0x2a9
fffff880`088b8530 fffff800`03388958 : fffffa80`0760ccd0 fffff800`00000000 fffffa80`079bab10 00000000`00000001 : nt!IopParseDevice+0x14d3
fffff880`088b8690 00000000`00000000 : 00000000`00000000 00000000`00000000 00000000`00000000 00000000`00000000 : nt!ObpLookupObjectName+0x588


STACK_COMMAND:  kb

FOLLOWUP_IP: 
nt!IoBoostThreadIoPriority+1e7
fffff800`030d45c7 418a442422      mov     al,byte ptr [r12+22h]

SYMBOL_STACK_INDEX:  3

SYMBOL_NAME:  nt!IoBoostThreadIoPriority+1e7

FOLLOWUP_NAME:  MachineOwner

MODULE_NAME: nt

IMAGE_NAME:  ntkrnlmp.exe

DEBUG_FLR_IMAGE_TIMESTAMP:  5147d9c6

FAILURE_BUCKET_ID:  X64_0xA_nt!IoBoostThreadIoPriority+1e7

BUCKET_ID:  X64_0xA_nt!IoBoostThreadIoPriority+1e7

Followup: MachineOwner
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