windows 7 - What issues could cause both stop codes of 7F and 116?

I'm working with a computer that had 3 recent BSODS. The first crash 3 days ago gave a 7F error with ntoskrnl.exe, which is hardly helpful. The crashes 2 and 1 day ago were with a 116 error, indicating video issues - bluescreenviewer listed dxgkrnl.sys. Could driver issues cause both error codes to intermittently happen? I cannot reproduce any of the BSODs.

EDIT:

7/2: 070215-32339-01.dmp 7/2/2015 1:11:48 PM UNEXPECTED_KERNEL_MODE_TRAP 0x0000007f 0000000000000008 0000000080050033 00000000000006f8 fffff808030c9888 ntoskrnl.exe ntoskrnl.exe+748c0 NT Kernel & System Microsoft® Windows® Operating System Microsoft Corporation 6.1.7601.18869 (win7sp1_gdr.150525-0603) x64 C:\Windows\Minidump\070215-32339-01.dmp 2 15 7601

7/3: 070315-23587-01.dmp 7/3/2015 11:49:48 PM 0x00000116 fffffa80037fe4e0 fffff88003e0c80c 0000000000000000 0000000000000002 dxgkrnl.sys dxgkrnl.sys+5d134 x64 C:\Windows\Minidump\070315-23587-01.dmp 2 15 7601

7/4: 070415-20794-01.dmp 7/4/2015 9:12:09 AM 0x00000116 fffffa8003c14180 fffff8800408780c 0000000000000000 0000000000000002 dxgkrnl.sys dxgkrnl.sys+5d134 x64 C:\Windows\Minidump\070415-20794-01.dmp 2 15 7601