- ASUS ROG Rampage IV GENE Motherboard Review
- Meet The Family - ROG Rampage IV Series
- A Closer Look - Design Highlights
- A Closer Look - Topology, I/O, and Power Delivery
- Features - UEFI BIOS
- Features - Software and Utilities
- Testing - Setup and Overclocking
- Testing - Storage and USB
- Testing - CPU and Memory
- Final Thoughts
- All Pages
A Closer Look - Topology and I/O
The back of the board has the same matte black finish, and we can see that the solder points are very clean and uniform. We can also see the separating line dancing in between solder points for the SupremeFXIII audio in the lower right corner, showing that ASUS wasn't trying to dupe you about it being completely isolated on the PCB. The VRM heatsink has a robust backplate which likely also has the benefit of providing a little extra cooling on the back side of the PCB.
Especially with such a small board and the connection requirements for quad-channel memory, laying out the PCB traces is both extremely difficult and immensely important. The layouts look very clean, and this image gives you a better look at the clean solder points on the back side of the DIMM slots.
The I/O options of the ASUS ROG Rampage IV Gene are pretty well-stocked and certainly don't leave you wishing you had a bigger board. In total there are 8 USB 2.0 ports (the white one is for ROG Connect), a PS/2 port for those who want N-Key Rollover (NKRO), an Intel Gigabit LAN port, two USB 3.0 ports, an optical SPDIF port, an e-SATA port which is tied directly to the PCH for hot-swap capability, and gold-plated audio connections to complement the SupremeFXIII audio. Additionally there are external buttons for CLR CMOS (the "refresh" arrow) and ROG connect (the button with the links). A big-boy loadout of I/O options for the myriad of accessories a the typical gamer would expect to work on a gaming-grade product.
Super Alloy Power and Extreme Engine Digi+ II
ASUS proudly touts its power delivery system, comprised of their Digital VRM design, Digi+, and their " Super Alloy Power," components abbreviated as "SAP." The VRM, which stands for "Voltage Regulator Module," is present on every motherboard and is responsible for converting the +12V provided by the power supply to the lower voltages needed by the CPU. This step down in voltage has a side effect of producing heat, and since the performance of capacitors and inductors which are responsible for providing clean voltage to the CPU are heavily dependent upon temperature, these components (and their associated cooling) can be critical to stability and overclocking headroom.
The VRM consists of a PWM, capacitors, chokes, and MOSFETs which steps down and stabilizes the +12V DC power from the PSU to the ~1V DC power neeeded by the CPU. The PWM (Pulse Width Modulator) is the controller which controls power delivery, and can be digital (more recent implementions) or analog (now becoming uncommon). ASUS' Digi+ design refers to the digital PWM which allows for greater control over power delivery options for both the CPU and DRAM, lower power response latency, and greater precision with voltage adjustments. Digi+ allows for almost complete control over the settings of the power delivery system, including phase frequency, load line calibration (LLC), finer frequency interval spacing, and presents a wide open playground for the tweaker (this kind of tweaker may or may not be into drugs) who wants to squeeze every last drop of performance out of their system. The Digital PWM is also what enables OS-side adjustments through a more intuitive and less-intimidatig UI (or even automatic overclocking), such as ASUS' MemTweak and TurboVEvo which has really brought overclocking to the masses.
The SAP chokes, capacitors, and MOSFETs are made from metals which are especially magnetic, heat-resistant, and anti-corrosive - translating into longer lifetimes and more reliable operation across the board. The MOSFETs are essentially the "transformers" which step down the voltage, and the inductors (chokes) and capacitors act as reservoirs/compensators to smooth out ripple or fluctuations to provide the CPU with "cleaner/filtered" voltage. The more efficient components also allow them to be downsized, which enables ASUS greater capability to optimize trace layouts on the PCB.
The capacitors use high-end Nichicon GT Black 10K capacitors which have better low-temperature endurance which ASUS claims will yield lifetimes 5 times longer than a standard capacitor. Many standard boards will use 2K caps, whereas the P9X79 channel boards use 5K caps. The chokes (inductors) have a higher current rating at 50A, which is 20A higher than a typical inductor. NexFET™ MOSFETs are rated for the same power rating as a standard MOSFET, but due to higher efficiency with better materials and productions processes, allows them to be literally half the size. The overall VRM design enables reduced thermal sensistivity, which can be especially important for a SFF build which may suffer from less-than-optimal airflow.
Another important factor is the number of phases used by the power delivery system. You can think of phases as parallel "rails" for delivering power to the various graphics card components, and the more rails you have, the more the power demand is spread out amongst the comonents, which means you have less demand on any given phase. The PWM controls power delivery across the phases by staggering power pulse peaks between the phases. ASUS uses an 8 Phase design for the CPU and a 2+2 Phase for the DRAM along with a 3 Phase VCCSA which is important for overclocking your BCLK which X79 still heavily-utilizes for overclocking. However, it's not as simple as "ye' board which hath the most phases doth be the noblest." Too many phases can have packed power circuitry and lead to thermal issues. ASUS uses a true 8-phase design, and the higher-amperage inductors allow a total of a whopping 400A (8 Phases * 50A). You could have a 12 or 16 phase design with 25A inductors which will be a consideration.