Reports from Chinese sources suggest that AMD’s Kaveri APU will definitely not utilise GDDR5 memory, instead they will carry on using DDR3. Different leaks in the past have suggested that we might see DDR3 or GDDR5, the main reason for the assumption that AMD may have chosen GDDR5 was due to how advanced the graphics portion of the Kaveri APU is becoming. However, GDDR5 will not surface so the Kaveri APUs are effectively limited to a 128-bit memory bus in terms of the graphics part.
That said AMD have significantly redesigned the memory controller to get the most out of the memory limitations and even though the new GPU will be powerful, it will not be powerful enough to warrant more than a 128-bit bus. Early reports suggested that the “best” AMD Kaveri APU part would be roughly equivalent to the recently released AMD Radeon HD 7730 graphics card. It is also worth noting that having to add in GDDR5 memory would do nothing for AMD except add in extra cost to the production process and they’d have to find a way of incorporating that GDDR5 into the APU platform – no easy challenge.
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