We must be very careful since ECS is calling all their motherboard with two PCI Express x16 as "SDGE" and this is causing a lot of confusion, especially because they didn't release any motherboard with the add-on module we described yet.
ECS is calling their SLI and Crossfire motherboards as "SDGE", even when they don't have the describe module, only because they have two PCI Express x16 slots - actually these slots run at 8x speed when SLI or Crossfire mode is enabled.
Worst is the case of the motherboards that don't have these technologies and are also being called "SDGE", like PF5 Extreme, which is based on Intel 945P chipset. Since this motherboard doesn't use the described architecture, the second PCI Express x16 slot is made by using spare PCI Express x1 lanes, hence the second x16 PCI Express slot can only run at best at 6x, since Intel 945P chipset has only 6 PCI Express x1 lanes. This is so true that when two video cards are used on this motherboard its PCI Express x1 slot cannot be used.
So, for ECS "SDGE" means "motherboard with capacity of having two PCI Express video cards at the same time".
We leave here a construtive critic to ECS: Why not using different names? Using the same name to define three distinct architecture causes nothing but confusion.