To be precise, I play Minecraft. When I play the game, it crashes, my system stops responding and weird patterns appear. I am forced to do a hard reeboot. Sometimes I even get a blue screen of death. I used bluescreenview, and the causes are dxgkrnl.sys, dxgmms1.sys and atikmpag.sys. Keep in mind, this never happened before, it only started today. I don't think it's an overheating problem(max temp. was 61 degrees celsius). Nor a psu problem because I am using a laptop. I do think I have to uninstall and then reinstall the video drivers but I can't find the software because I have 2 graphics cards( AMD Radeon HD 7640G+7670M). Can someone please identify the issue?

Your issue is DX related and has been discussed before - handy things these free forum search tools

So install this: http://download.microsoft.com/download/8/4/A/84A35BF1-DAFE-4AE8-82AF-AD2AE20B6B14/directx_Jun2010_redist.exe

And then run this whether or not it succeeds or fails: http://www.microsoft.com/download/en/details.aspx?id=35

If that doesn't work nor does a system restore or anything else, then you could try a fresh Windows install or talk to the laptop manufacurer's tech support as that's the fix I do for desktops at work and things might be different for laptops etc.

The driver software you need to run that laptop correctly would be on the download page of said laptop .. go to the manufacturer website, find your machine, find the driver download page and voila ..

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