GPU rendering is what allows using graphics card for rendering, instead of CPU. This helps speeding up rendering, because modern GPUs are so designed to do quite a lot number crunching. Further, they also carry with them limitations in rendering complex scenes, due to extra limited memory and issues with interoperability while using same graphics card for display and rendering. Cycles that are currently in trend and followed by many have the ability to render
projects on GPUs. It allows upto 10 times faster rendering speed than using the CPU. However, rendering large cycles animations can prove to be time consuming, in case of unavailability of lots of machines with powerful GPU’s.
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