How to detect the presence of a Multi Stream Transport hub under Windows?
If a Thunderbolt device has two display outputs, it might take both DisplayPort signals off the bus or it might be using an MST hub. Is there any way to tell which one it is? Aside from, of course, trying to connect two 4k @ 60Hz monitors.
Linux has DP branch device info on debugfs. What about Windows?
Solution 1:
You could find the number of monitors and used lanes by using the free TechPowerUp GPU-Z.
Under the Advanced tab, you will find the monitors and the number of lanes taken by each one. From this data you may find the number of DisplayPort signals taken off the bus:
