Suddenly Screen went Black and then Reboot (Often)

[franksteven953]

Almost every time my system suddenly get a black screen and reboots (varies from 5 minutes to hours before reboot).
After every reboot comes a box "Windows has recovered from an unexpected shutdown" with this message

Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.1.7601.2.1.0.768.3
Locale ID: 1033

Additional information about the problem:
BCCode: 116
BCP1: FFFFFA80068844E0
BCP2: FFFFF88006450DC0
BCP3: FFFFFFFFC000009A
BCP4: 0000000000000004
OS Version: 6_1_7601
Service Pack: 1_0
Product: 768_1

Files that help describe the problem:
C:\Windows\Minidump\022215-12682-01.dmp
C:\Users\(Username)\AppData\Local\Temp\WER-27346-0.sysdata.xml

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From a quick look, the BSOD code seems to point a graphic problem.
I have tried to uninstall NVIDIA driver, cleaned the remaining of the driver and perform a clean installation of the NVIDIA driver.
Any ideas? I hope the idea doesn't require re-installation of Windows as I may lose some data.
Thanks.

Quick specs:
Intel Core i5-2500
NVIDIA GeForce GTX 550ti by Gigabyte (GV-N550WF2-1GI)
WD Blue 500GB
RAM 8 GB
Gigabyte GA-P75-D3
PSU 500W (included with the case)

 

[franksteven953]

Current NVIDIA driver: 347.25 release