Computer help forum: Strange crashes

I experience some strange crashes. They appear strange because they are different and seemingly random.

For a period of time, I have tried to fix the issues - some of them are gone: one was caused by the monitor.
I reformatted my C drive (I didn't reformat my secondary hard drive, which still contains some junk)

But the computer still crashes.
I have experienced that the image suddenly freezes completely, and if sound was playing at the moment, it warps completely and noisily (sounds scary actually). It's hard for me to see any connection between the freeze and the thing I was doing on the computer.
Sometimes I see the blue screen after such a freeze, and afterwards, the computer might have trouble booting. Then sometimes, while booting, I notice the monitor resolution is very low, and most oddly, there are visual anomalies also. They are red or green, and they appear "systematically", like patterns. here there is a link to a picture that shows such an anomaly:
http://www.mediafire.com/view/?u7wfj3b7a0rtobw

A few times, a message appears when the computer finally boots succesfully. the latest crash, today, annoyed me beyond sanity, and now I have signed up to this forum. I saved the info from the message:

Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.1.7600.2.0.0.256.1
Locale ID: 1030

Additional information about the problem:
BCCode: 116
BCP1: FFFFFA8008AE84E0
BCP2: FFFFF880051A3B10
BCP3: FFFFFFFFC000009A
BCP4: 0000000000000004
OS Version: 6_1_7600
Service Pack: 0_0
Product: 256_1

Files that help describe the problem:
C:\Windows\Minidump\011713-17796-01.dmp
C:\Users\Antonius\AppData\Local\Temp\WER-46703-0.sysdata.xml

Read our privacy statement online:
http://go.microsoft.com/fwlink/?linkid=104288&clcid=0x0409

If the online privacy statement is not available, please read our privacy statement offline:
C:\Windows\system32\en-US\erofflps.txt

Now, looking on the internet for a solution, I came across a command that starts a reliability test "perfmon /rel"

Here I get a list of the crashes there has been since christmas where i reformatted.
The crash from ealier today is listed like this:

Windows stopped working at 13.46
Video hardware error at 13.46
Video hardware error at 13.46
Video hardware error at 13.46
Video hardware error at 13.46
Video hardware error at 13.46
Video hardware error at 13.46
Shut down unexpectedly at 13.47
Windows was not properly shut down at 13.52

The last two is probably me holding the power button.

Windows stopped working
Description
The computer has rebooted from a bugcheck. The bugcheck was: 0x00000116 (0xfffffa8008ae84e0, 0xfffff880051a3b10, 0xffffffffc000009a, 0x0000000000000004). A dump was saved in: C:\Windows\MEMORY.DMP. Report Id: 011713-17796-01.

Some of the video hardware errors descriptions are empty.

others:

Problem: Video hardware error
Files that help describe the problem:
WD-20130104-0402.dmp
sysdata.xml
WERInternalMetadata.xml

Files that help describe the problem:
WD-20121230-0010.dmp
sysdata.xml
WERInternalMetadata.xml

Files that help describe the problem:
WD-20121229-2211.dmp
sysdata.xml
WERInternalMetadata.xml

I don't know if the little variations matter or if its just the same. It seems to be a problem with my graphics card, but I would like to know if the problem could lie elsewhere. I wouldnt buy a new graphics card unless I'm sure.
Please help me solving this issue. I'm soon going crazy from trying to figure out this problem myself.