Last entries in your log:
04:36:21.284: Device Remove/Reset! Rebuilding all assets...
This message is issued if the display driver of your system crashes. Usually a hardware issue with the GPU, may be some component in your somewhat older PC got defective. GPU itself, or may be the power supply. Revert any overclocking.
You might try removing and reinstalling the newest display driver for your GPU, but I guess it's more a hardware thing.