I'm leaning towards memory. I think that the MB has 1.5v memory slots. You have 1.65v memory. There may be some type of memory issue with this. 1155 officially only supports 1.5v.
Is you memory on this list.http://download.gigabyte.eu/FileList/Memory/mb_memory_ga-b75-d3v.pdf
My memory is not on that list. My model is KHX1600C9D3B1/4G.
If I am going to change it tommorow, what's the model that I'll use as a replacement?
I am running Windows 7 32 bit if it's relevant.
I'll run the stress tests now.