SupremeFX has been a staple addition to Republic of Gamers motherboards ever since the very first Crosshair. Its design is focused on improving sound quality beyond the standard that most motherboards included, by putting the audio onto a separate sound card that plugged into a PCIe x1 slot. Isolating the analogue sounds in this way helped improve audio quality. In the intervening 5 years, SupremeFX has evolved into its third revision. First added to the Rampage IV Series late last year, it's now following onto the Maximus V GENE as well.
The Red Line - Continuing the trend of audio isolation
SupremeFX III may have stopped being a separate PCIe sound card, but it still keeps the audio isolation requirement at its heart. This is signified by the 'redline' on the PCB, which highlights the physical separation of the audio processing from the rest of the motherboard. The PCB itself is actually see-through, where the red lighting is produced by a row of LEDs on the back of the PCB that then shine through giving it a subtle glow. Incorporating the audio codec on the motherboard itself means that you get an extra PCIe slot to upgrade, or in the case of the GENE series, no sacrifice in multi-GPU potential due to limited expansion space (which was also a reason for the development of the mPCIe Combo card).
Despite the PCB separation, the SupremeFX III hardware still draws its power (and data) from the motherboard at one point, which means some conditioning is required to the input power feed that is always shared with other motherboard hardware. This large 1500uF cap performs two functions, firstly it helps to smooth the incoming power feed, reducing jitter that can compromise sound quality, and secondly it provides a big buffer just in case the game, music or movie produces a loud, powerful sound. When pushed through line powered speakers or headphones (i.e. those that have no additional socket/battery power for the speakers) the sudden power draw can cause audio clipping, which the large capacitor aims to prevent.
EMI aluminum cap
The codec itself is kept under an aluminum cap which helps isolate it from surrounding EMI. The inside of your PC case is subject to many different high-frequency interferences, which can constructively or destructively affect the audio output. Modern hardware has reduced its effect by lowering voltages, improving construction and with better PCB design; in part by placing the audio processor at the furthest corner of the PCB helps isolate it further. However, the effect will be negated if you sit a powerful graphics card and fan right on top of it in a multi-GPU environment (or if you happen to use lower PCIe 16x slots for your primary card). The EMI shield helps create a barrier to this, further benefiting SNR.
Gold plated audio jacks
A common feature on higher-end audio cards, but one not necessarily found on most motherboards due to cost - gold plating helps improve the electrical connection between 3.5mm audio jack and the socket, and also prevents environmental corrosion. The latter is more significant to those who live in hot and humid countries or within the winds distance to the ocean, as these accelerate corrosion.
THX® TruStudio™ PRO
The software enhancements THX are still included with SupremeFX III. For those that want them they are an optional software install from the included motherboard driver disc. Click the links for more information about THX TruStdio Pro. You can see more about ROG sound technologies on our innovations page.