Gigabyte uses an AWARD BIOS for the GA-8N-SLI, that is both similar to most users, but at the same time unique. The main menu options are straight-forward and point you directly to the BIOS sections you are looking for. Typical of most Gigabyte motherboards, hitting CTRL-F1 brings up a few extra options usually reserved for the most hardcore tweakers and/or overclockers.
For the most part, setting up the basics of a system requires determining which onboard devices to enable such as the audio CODECs, single or dual LAN jacks, or even the legacy ports. Standard rule of thumb says if you won't be using that port then it's best off to leave it disabled. Drive options are numerous, befitting the SouthBridge's abilities, ranging anywhere from single drive setups to multi-disks in a RAID array. Once these options are decided, it's always best to take a quick peek into the health of your PC, which visually displays temperatures, voltages, and fan speeds. If anything appears out of whack, you should check into correcting the problem before continuing further.
Assuming everything is running correctly, it's time to get to the real meat-and-potatoes of the BIOS, a screen called the M.I.T., short for the MB Intelligent Tweaker. Keeping with the not so cryptic nomenclature, the first two options to look into are C.I.A.2 and C.A.M. C.I.A.2, or CPU Intelligent Accelerator 2, is Gigabyte's version of an automatic overclocking utility that only kicks in when the CPU is running full throttle for 10 seconds or more. There are varying degrees that can be set, starting from Cruise and going up to Full Thrust mode, which aims to overclock the CPU by about 17-19%. C.A.M. is probably less useful for most users, as it only allows users of unlocked CPUs to set the clock ratio to High or Low.
Of course, many users will want to find out the limits of their system on their own, so rather than enable C.I.A.2 they will want to go the System Clock Mode and choose either Linked or Expert Modes. Linked allows the user to raise the clock speed, but doing so will raise the CPU and Memory at the same time. Expert, on the other hand, allows the clocks to be raised asynchronously. Separate speeds can be entered so that the CPU, Memory, or both are left at their original speeds or overclocked. Gigabyte allows the user much freedom in the way the GA-8N-SLI is used.
More advanced options are available further down the M.I.T. page, some of which are expected, but at least one requires a little forethought. As the GA-8N-SLI technically supports up to 5 graphics cards, there needs to be a way to decide which one is the primary adapter. Any card can be selected, although PEG Slot 2 is, by default, the first choice. This means, contrary to most builds, the card should be installed in the second PCI-e slot, rather than the first to get optimal performance. Installing more than one card involves the installation of the paddle board, but also a little tweaking in the BIOS as well. Depending on which way the SLI card is installed determines the slot lane configuration options. For the majority of us, choosing 1-16-16-1 here will result in enabling 16 PCI-e lanes for PEG slots 2 and 3 - perfect for single card or SLI configurations.