That build is known for it's appearances at repair counters. You usually find replacing motherboard and video card can clear it up for a time but you left out the power supply from the list. You want a PSU with 1.5 to 2 times the needed power with a single rail.
If the freeze thaws it usually points to HDD issues. We always run the CHKDSK /F/R/X and hope that clears it up but if not we clone the drive to a new HDD and see if that clears it up.
For about half a year now, my computer has gone through periods where it randomly freezes up. About every week to 2 weeks, my computer will freeze for up to 3 minutes at a time at intervals of once every 10 minutes to once every 3 or 4 hours. These freezes generally come in varying intensities.
The first intensity, which I'm calling a 'soft freeze' occurs where a webpage or program will stop responding to inputs. Although I can still move the mouse, clicking does not change anything with the computer. Audio from videos continues to play until it reaches the edge of what was buffered.
At other times, graphics on the computer will freeze completely, yet the computer continues to communicate with background programs such as discord and teamspeak, meaning I can talk to friends while this is all going on, but that's about it.
Finally, the computer will sometimes freeze up and stop communicating with any programs, sometimes even powering down by itself. Rarely, about 5 seconds of the audio clip that was playing at the time will loop repeatedly until the computer either unfreezes or shuts down.
As this problem has occurred across multiple programs and my drivers are updated, this does not appear to be a software issue. I have not overclocked any of my components. I use an open air case with several fans, so overheating is also not an issue. While the open air case initially led me to believe this was a dust problem, treatment with a duster had little effect.
A stress test with Prime95 for about 12 hours turned up no problems, however of curiosity is that one core only completed about 30 tests in this time period while the other 3 completed about 100.
I also suspect this might be a graphics card problem as the computer is able to do things such as communicate with audio programs most of the time.
Specs are as shown:
Processor: AMD FX(tm)-4170 Quad-Core Processor 4.2 GHz
Installed memory (RAM): 8.00 GB
System type: 64-bit
OS: Windows 7 Home Premium
Graphics Card: AMD Radeon HD 7800 Series
TL;DR:
My computer randomly freezes and I suspect that the problem lies in the graphics card. Does anyone know of tests that can verify this?

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