The BIOS and Overclocking
Gigabyte has outfitted the GA-N680SLI-DQ6 with a customized Award / Phoenix BIOS derivative that resembles many of the other high-end, enthusiast class motherboards currently on the market. Gigabyte does, however, put their own spin on the BIOS, which isn't necessarily for the better...
The boot screen hints at many of the GA-N680SLI-DQ6's proprietary features and technologies mentioned previously. The main BIOS menu screens should look familiar to many of you. Using these menus, users can configure any of the board's integrated peripherals, set the boot order, or tweak memory timings, etc. This is all good, but one thing Gigabyte has been doing for a while still irks us a bit. To access all of the advanced features inherent to this motherboard's BIOS, users are required to press CTRL-F1 after entering the BIOS. Doing so reveals a number of menu options that aren't available without pressing this key combination. This isn't a huge issue, but it is an annoyance considering this is unquestionably an enthusiast-class board, and enthusiasts are going to want access to every feature by default without having to take special measures.
The MB Intelligent Tweaker, or M.I.T., menu is where experienced users will find all of the GA-N680SLI-DQ6's voltage and memory options, and overclocking tools. Although the motherboard is based on NVIDIA's nForce 680i SLI chipset, Gigabyte does not use the standard BIOS menus found on many other reference 680i boards, like EVGA's or XFX's. With the GA-N680SLI-DQ6, Gigabyte took it upon themselves to customize the overclocking menus, and while it is well organized, NVIDIA's reference BIOS is a little better in our opinion.
With that said, the M.I.T. menu does give users plenty of control over voltages and frequencies for the CPU, chipset, and memory. There is fine granularity with all of the voltage controls (which are extensive) and all frequencies can be adjusted in 1MHz increments.
We spent some time overclocking our Core 2 Duo X6800 processor with the GA-N680SLI-DQ6 motherboard and had very good results. Before we began, we bumped the CPU and chipset voltages up by a tenth of a volt, configured our memory to operate at 400MHz, and dropped the CPU's multiplier. Then we raised the FSB until the machine was no longer stable. In the end, we were able to hit a stable FSB frequency of 478MHz (1.91GHz quad-pumped). This is an excellent result; the GA-N680SLI-DQ6 is definitely a motherboard that's well suited to overclockers.