Now to the overclocking side of the equation.
The 8N-SLI Royal is setup as one of Gigabyte's mainstream boards with quite a few overclocking options inside. In terms of the features, it's almost a mirror layout of the 8N-SLI Quad Royal with a few voltage changes. Some of the descriptions in this section will be the same as the 8N-SLI Quad Royal review, as some of the settings are exactly the same.
First is CPU Ratio control. For Pentium Extreme Edition CPU owners this is where you will change the multiplier as this is one of the benefits of spending a lot of cash on a processor.
On all of Gigabyte's top model boards is the C.I.A.2 automatic overclocking feature. In the C.I.A.2 setup you have Cruise, Sports, Racing, Turbo and Full Thrust options, which overclock the CPU to a set percentage when the load on the CPU is 100% for 10 or more seconds. You can disable this to overclock the FSB manually.
FSB turbo mode is used to keep the FSB from fluctuating when under load; this option should be disabled for manual overclocking, as it tends to cause instability in the system.
System Clock mode is where you start to manipulate memory and FSB speeds. There are three options here. Optimal prevents any changes by the user. Linked mode keeps the memory clock and FSB linked, so any FSB increases overclocks the memory. In Expert mode, the FSB and memory clocks work asynchronously; this means you can input any FSB speed and the memory will stay at the specified speed the user inputs. And vice versa, if you want to overclock the RAM and not the FSB, you simply change the RAM speed and the FSB remains the same.
In order to get to the voltage settings you need access the Advanced Voltage Control sub-menu of the M.I.T menu. The first setting is the CPU voltage. You can adjust the voltage range from 1.0v up to 1.75v in 0.0125v increments. This allows you to use Presler, Prescott, Smithfield and Gallatin cores and give them all a pretty good voltage boost for your overclocking needs.
Next is DIMM voltage. This has been a pretty sore point in Gigabyte's past, as they simply haven't given enough voltage in order to overclock to extremes. The 8N-SLI Royal breaks this rule. You can adjust from default voltage up to a max of +0.55v in 0.05v increments. In real world voltage this means you can go from DDR-2's default of 1.8v up to 2.35v, not the highest we have seen, but for quite a few DDR-2 modules out there on the market, it's more than enough. OCZ memory is rated to 2.2v DDR-2 and still warranted, so this board gives just that bit extra for headroom.
Next is the Northbridge voltage. This is used in order to stabilise the Northbridge, PCI Express x1 ports and the first two PCI Express x16 ports when overclocking. You can set it from default up to +0.55v in 0.05v increments. This gives from 1.5v up to a max of 2.05v.
Following the Northbridge voltage is - you guessed it - Southbridge voltage. This is also used to stabilise the Southbridge. You can raise the voltage from default up to a max of +0.55v in 0.05v increments. This gives you the same as the Northbridge, 1.5v up to 20.5v.
Front Side Bus Overvoltage is next on the list. This one is used to give the Netburst bus an extra voltage jump when overclocking. You can adjust the FSB Overvoltage from its default up to a max of +0.175v in 0.025v increments. This means you get from 1.2v up to 1.35v.
Lastly in voltage there is the SATA-II Overvolt. This gives extra power to the SATA bus when overclocking it. You can adjust this from default to a max of +0.3v. We aren't sure of its default voltage, so we can't give a readout on what the final voltage is.
There is one final sub-menu in the Gigabyte M.I.T setup. This is called the Advanced Frequency Control Menu. Here there are two extra options. First is the PCIe Frequency control. You can set the PCIe Frequency from 100MHz to a maximum of 200MHz in 1MHz increments. PCIe buses are extremely sensitive to overclocking and cause the most instability in overclocked situations. PCIe is known to fail at even 7% overclocks. Best idea is to leave it at 100MHz to keep all PCIe devices at stock speeds.
The final option is the LDT Frequency. AMD users will know this setting; it is used to control Hyper Transport multipliers. Now a lot of people might ask why there is an AMD Hyper Transport used on the Intel system. Hyper Transport is used to interconnect the North and Southbridges. They are clocked using the exact same setup as the AMD Athlon 64 CPU to External Northbridge at 800MHz, 600MHz and so on. This gives the most robust and fastest interconnect speed of any chipset out there on the market. Under this menu you have the ability to change the multiplier from 1x up to 5x. This gives you a 1600MT/s connection between to the two chipsets.
With this setup we placed a Pentium D 840 into the system to test the overclocking ability. We managed 313MHz with 1.45v CPU, 2V DIMM, 1:1 RAM ratio, and all other voltages stock - a pretty good effort for sure.