The Gigabyte GA-8N-SLI Quad Royal features four physical PCI Express x16 slots, and that is the really selling point of this motherboard. Just the idea of quad SLI is tantalizing, but at the moment only two videocards can run in SLI at any given moment. This may change in the future, but for the moment current Forceware 81.98 drivers users are still limited to two videocards in SLI.

The manufacturer has colour-coded the PCI Express x16 slots to make it clearer which ones will provide 16 PCI Express lanes or just 8 PCI Express lanes to the graphics cards. To get the best out of the GA-8N-SLI Quad Royal motherboard when running SLI, the two center blue PCI Express slots are used.

With these slots, each videocard receives a full 16 PCI Express lanes. Normally, a single nForce 4 SLI chipset would not have enough PCI express lanes available to it for such a split, but on this board the top slot belongs to the nForce4 SLI Northbridge and the bottom slot to the nForce4 SLI Southbridge. For optimal performance, you'll need to connect the SLI bridge connector between both videocards naturally. The SLI selector card may need to be flipped around too, depending on what you want the motherboard to do.

If you choose to run SLI videocards in the first two slots (one black, one blue), the selector card between PCI Express x16 slots one and two must be set properly to allocate the right amount of PCI Express lanes to each videocard. If SLI is to be run in the bottom two physical PCI Express x16 slots (one blue, one black), there is no user manipulation required since Gigabyte equips the Southbridge slots with the Pericom chips which automatically sense when two SLI videocards are installed.

The Pericom chipset takes care of the PCI Express bus splitting and it would have been nice if Gigabyte could have done the same for the two top PCI Express x16 slots too, but I suppose there is a technical reason why this was not done.

Now here is where it get a little complex; if the Gigabyte GA-8N-SLI Quad Royal has three or four videocards installed, SLI cannot be enabled. While the nVIDIA drivers recognize that there are SLI compatible videocards installed, it asks that the other videocards be removed first. Hopefully in the future, nVIDIA will allow SLI to be enabled with more than two videocards. ;-)

Possible SLI Configurations on the GA-8N-SLI Quad Royal nForce4 SLI Intel Edition Northbridge nForce4 SLI AMD Edition Southbridge SLI Enabled Physical PCI Express x16 Slot 1 Physical PCI Express x16 Slot 2 Physical PCI Express x16 Slot 3 Physical PCI Express x16 Slot 4 nVIDIA Videocard (PCI-E x8) nVIDIA Videocard (PCI-E x8) Yes nVIDIA Videocard (PCI-E x8) nVIDIA Videocard (PCI-E x8) Yes nVIDIA Videocard (PCI-E x16) nVIDIA Videocard (PCI-E x16) Yes nVIDIA Videocard (PCI-E x8) nVIDIA Videocard (PCI-E x8) nVIDIA Videocard (PCI-E x8) nVIDIA Videocard (PCI-E x8) No

With SLI disabled and four videocards installed, the Gigabyte GA-8N-SLI Quad Royal can support up to eight digital monitors! There are certain games that support more than one monitor, and in this case it's pretty spectacular to just imagine playing Microsoft Flight Simulator!

We are going to show you all the possible SLI and videocard combinations next.