BSOD on New PC

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 7 Ultimate, Service Pack 1, 64 bit
Processor: AMD FX(tm)-8350 Eight-Core Processor, AMD64 Family 21 Model 2 Stepping 0
Processor Count: 8
RAM: 8156 Mb
Graphics Card: NVIDIA GeForce GTX 770, -2048 Mb
Hard Drives: C: Total - 244195 MB, Free - 168312 MB; D: Total - 3815317 MB, Free - 3776782 MB;
Motherboard: Gigabyte Technology Co., Ltd., 990FXA-UD3
Antivirus: Microsoft Security Essentials, Updated and Enabled

I keep getting BSOD and can't figure out how to fix the problem. The common theme seems to be ntoskrnl.exe, whatever that is. Here's some dumps from the three times it's happened so far.

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Dump File : 050814-10342-01.dmp
Crash Time : 5/8/2014 9:20:20 PM
Bug Check String : NTFS_FILE_SYSTEM
Bug Check Code : 0x00000024
Parameter 1 : 00000000`001904fb
Parameter 2 : fffff880`0334d5e8
Parameter 3 : fffff880`0334ce40
Parameter 4 : fffff880`012d9279
Caused By Driver : Ntfs.sys
Caused By Address : Ntfs.sys+8a279
File Description : NT File System Driver
Product Name : Microsoft® Windows® Operating System
Company : Microsoft Corporation
File Version : 6.1.7600.16385 (win7_rtm.090713-1255)
Processor : x64
Crash Address : ntoskrnl.exe+75c00
Stack Address 1 :
Stack Address 2 :
Stack Address 3 :
Computer Name :
Full Path : C:\Windows\Minidump\050814-10342-01.dmp
Processors Count : 8
Major Version : 15
Minor Version : 7601
Dump File Size : 292,784
Dump File Time : 5/8/2014 9:23:36 PM
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Dump File : 042314-10732-01.dmp
Crash Time : 4/23/2014 11:18:52 PM
Bug Check String : SYSTEM_SERVICE_EXCEPTION
Bug Check Code : 0x0000003b
Parameter 1 : 00000000`c0000005
Parameter 2 : fffff960`0028293a
Parameter 3 : fffff880`077c5120
Parameter 4 : 00000000`00000000
Caused By Driver : win32k.sys
Caused By Address : win32k.sys+23293a
File Description : Multi-User Win32 Driver
Product Name : Microsoft® Windows® Operating System
Company : Microsoft Corporation
File Version : 6.1.7600.16385 (win7_rtm.090713-1255)
Processor : x64
Crash Address : ntoskrnl.exe+6f880
Stack Address 1 :
Stack Address 2 :
Stack Address 3 :
Computer Name :
Full Path : C:\Windows\Minidump\042314-10732-01.dmp
Processors Count : 8
Major Version : 15
Minor Version : 7600
Dump File Size : 292,728
Dump File Time : 4/23/2014 11:19:54 PM
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Dump File : 042214-13993-01.dmp
Crash Time : 4/22/2014 2:38:10 AM
Bug Check String : PAGE_FAULT_IN_NONPAGED_AREA
Bug Check Code : 0x00000050
Parameter 1 : fffff900`c365ec68
Parameter 2 : 00000000`00000001
Parameter 3 : fffff960`002423a6
Parameter 4 : 00000000`00000000
Caused By Driver : ntoskrnl.exe
Caused By Address : ntoskrnl.exe+6f880
File Description : NT Kernel & System
Product Name : Microsoft® Windows® Operating System
Company : Microsoft Corporation
File Version : 6.1.7601.18113 (win7sp1_gdr.130318-1533)
Processor : x64
Crash Address : ntoskrnl.exe+6f880
Stack Address 1 :
Stack Address 2 :
Stack Address 3 :
Computer Name :
Full Path : C:\Windows\Minidump\042214-13993-01.dmp
Processors Count : 8
Major Version : 15
Minor Version : 7600
Dump File Size : 292,728
Dump File Time : 4/22/2014 2:41:09 AM
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