Rivals: Sandy Bridge, Optimus...
X-bit labs: Intel Corp.'s Sandy Bridge processor manages to offer dramatically higher graphics performance thanks to improvements of the graphics cores as well as due to unified L3 cache for x86 and graphics core. However, you skipped unified L3 in case of both Llano and Ontario/Zacate. What are the reasons for that? Perhaps, common core interface is more efficient than what Intel uses?
Godfrey Cheng: I do not know a lot about Sandy Bridge architecture; but that type of cache/memory implementation will not be efficient for our architecture. We are basically took a discrete GPU and married it with a very good CPU and that type of architecture basically demands us to make considerations and decisions that are within memory controller and also how we use external memory. Using L3 might work well for Intel, but it will not work well for us, which is why we are diverging in this area.
X-bit labs: Did you consider a technology similar to Nvidia Optimus that would dynamically switch from integrated graphics to discrete within a Fusion platform?
Godfrey Cheng: The Optimus is an interesting technology. We have PowerXpress, which is a similar technology [ATI PowerXpress allows notebook users to manually or automatically switch between an ATI Mobility Radeon HD discrete graphics processor and an integrated AMD M780G with ATI Radeon HD 3200 graphics without rebooting their notebook]. What we have not been discussing broadly so far is that you get a lot of synergy between a Llano APU and a discrete GPU. What we were able to make close together works better than one plus one.
X-bit labs: But the GPU integrated into Llano APU consumes a lot less power than a standalone graphics processor...
Godfrey Cheng: Fairly, we have invested heavily to make sure that we do the right thing with power gating and so forth. The point is that when you plug in an AMD APU and an AMD GPU, you get better performance than you would with the same GPU and an Intel processor.