For info, the dumps do show SP1 installed.
For ATI, the dumps show
AtiHdmi.sys Wed Apr 22 05:49:04 2009 (49EEE810)
atikmdag.sys Tue Apr 28 22:23:36 2009 (49F7BA28)
Vista comes installed with DirectX 10, which DXDiag reports as 9.0c. All Vista systems come with the necessary installed software for DirectX 10.1 as well, but can only be addressed if the video card supports it. I have noticed on my Vista systems since the installation of SP2 that DX 10.1 appears on some of the various system reports.
Be sure that your Realtek NIC is updated. Per the dumps -
Rtlh64.sys Mon Jun 25 01:37:13 2007
A bugcheck = 0x50 more times than not is RAM related (installed or video), especially when win32k.sys is mentioned. This tells me that the system failed during a transition from user-mode into kernel code territory -- a task that video does perform among others.
Run memtest86+ (it does support x64) - https://www.memtest.org/
1 stick at a time, alternate slots.
Burn memtest bootable CD with ImgBurn - https://www.imgburn.com/index.php?act=download
The fact that the DirectX kernel was named as the probable cause in a BSOD leads me to believe that it was most likely left at the scene of the crash to take the blame and the real culprit was hidden by the DX memory address range. If true, the driver verifier may be able to help by flushing out the rogue driver -
You may also want to test RAM by gradually reducing it -- take out 1 stick, then test; take out another, etc... until 1 remains. Then alternate slots and see if BSODs continue. Perform this test playing the game in question.
Lastly, what is the origin of the Vista installation? Do you have a retail version of Vista or an OEM version (Dell, HP, etc...)? Re-validate your Vista installation - go to Microsoft Genuine Advantage (1st button on left side about 1/4 page down) -
Regards. . .