Released in 2012, the Toshiba Satellite C850 is a 15.6-inch notebook with a choice of either AMD or Intel processors. It has USB 3.0 and can be configured with up to a 1TB HDD for storage and discrete graphics.
lewis, attach an external monitor and see if it has the same discoloration. If it does its the GPU on your logic board and it is not repairable by a normal DIY'er. If it does not show the discoloration, replace your computers LCD. Here is the guide for it.
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