HBC is an acronym for High Bandwidth Cache, a proprietary video memory and caching design on AMD Radeon Vega architecture based graphics cards.
AMD’s HBC features two components. The HBC itself which is video memory such as HBM2 or GDDR5 along with the HBCC, or High Bandwidth Cache Controller. Generally speaking, when referring to HBC, you’re referring to both HBC and HBCC.
What makes HBC special is that it provides intelligent video memory management making the utilization of a graphics cards’s onboard memory frame buffer much more efficient. According to former AMD Radeon Technologies Group SVP and Chief Architect, Raja Koduri, most games only utilize about half of the video memory allocated. The reason for this is that developers allocate more memory for their games and applications as running out of video memory drastically decreases user experience.
However, by using HBC, AMD is able to significantly decrease the amount of video memory allocated by intelligently managing video memory for the application, effectively doubling the amount of usable graphics memory. This is important as more complex textures, VR, 4K and 8K gaming require significantly more video memory than ever before and making things more efficient will allow developers to create even more complex, even more photo-realistic graphics in real-time.