I'm referring to the 2015 Macbook Pro, 15-inch, with the AMD Radeon R9 M370X with 2GB GDDR5 memory. Can this drive two Ultra HD monitors (3840 x 2160) at 60FPS each? If so, would you be able to simultaneously use the built-in display?
To be clear, I'm referring to SST (single-stream transport) monitors, not MST (multi-stream transport).
You'd have to plug each monitor into a Thunderbolt port, since HDMI supports only 30FPS. Are both Thunderbolt ports on different Thunderbolt buses, or the same? In the latter case, there may not be enough bandwidth.