PCB Design and Features
The Maximus IV Extreme offers so many features, technologies and innovations that we are quite confused as to what to begin with. Well, let’s start out from the basics. The mainboard is based on the Intel P67 Express chipset (B3 revision) and supports newest LGA1155 processors. The CPU voltage regulator has eight phases; there are also three power phases for the memory slots.
Unlike ordinary digital VRM design, the Asus voltage regulator combines the advantages of both: the digital and analog VRM designs, delivering less switching delay while offering better accuracy at the same time. The circuitry is built with solid-state FPCAP capacitors from the japanese Fujitsu Company. For additional core voltage filtering they installed one NEC/TOKIN Proadlizer capacitor, which we have already seen on EVGA Classified mainboards and non-reference MSI (Lightning series) and Gigabyte (Super Overclock series) graphics cards.
The hot components of the CPU voltage regulator are covered with two heatsinks which are connected with heat pipes to the central heatsink which sits on an Nvidia NF200 chip. Every heatsink, including the one on the chipset, is secured with screws.
The mainboard offers one PCI Express 2.0 x1 and one PCI Express 2.0 x4 slot. The latter isn't very popular, but you may need it to install additional disk controllers or even a disk itself (e.g. an OCZ RevoDrive). There are also four PCI Express 2.0 x16 slots that allow building CrossFireX and SLI configurations. The speed formula of the graphics slots is not trivial, though.
The P67 Express chipset is able to support one discrete graphics card in full-speed PCIe x16 mode or two such cards in x8 mode each. The lower interface bandwidth in the second scenario is only going to show up at high display resolutions, but such compromises are unacceptable with flagship products such as the Maximus IV Extreme. Therefore this mainboard is equipped with an additional Nvidia NF200 controller to accelerate the graphics slots whereas the PLX PEX 8608 bridge increases the number of PCI Express lanes even further. The operation of the graphics slots is somewhat complicated and is best illustrated with the table from the user manual.
So, a single graphics card installed into the first slot works in full-speed PCIe x16 mode, just as expected. Adding a second graphics card into the third slot does not change anything in the chipset's standard behavior: the slots begin to work in x8 mode each. It's only with a third graphics card that the Nvidia NF200 controller is triggered on, and you should install the second and third cards into the second and fourth slots. The first slot will still be working in x8 mode but the other two, in full-speed x16 mode. So, it looks like you can get the most from the Maximus IV Extreme in terms of graphics performance only if you install as many as three graphics cards on it. Well, of course you can have only one or two graphics cards, but you won't be using the NF200 controller then and you won't be able to even turn it off. The mainboard has two 4-pin power connectors especially for the graphics card slots, but the bottom one is positioned horizontally and you may find it hard to plug a connector into it.
Most of the extra components can be found in the mainboard's top right corner. There are highlighted Power and Reset buttons here. The Go button serves two purposes. If pressed before turning the mainboard on, it enables the MemOK! feature that helps start the system up in case of some memory-related problems. If pressed while the mainboard is working, it applies the frequency, multiplier and voltage settings entered in the BIOS's Go Button File page. In other words, it allows overclocking the system instantly to the predefined parameters. The four DIP switches can be used to turn off any of the four graphics slots. The ProbeIt contact points help you manually measure the key voltages (there are special cables included into the box for making the measurement process easier). A POST indicator is in the corner next to the LN2 Mode switch which is supposed to be enabled for extremely efficient cooling systems (this switch helps avoid the so-called cold bug; it's when the system doesn't start up due to the CPU having a very low temperature).
If the LN2 Mode switch doesn’t help, you can bring your system back to life with the Q Reset button located near the back-panel connectors. There is another button in the bottom right corner of the PCB for switching between the mainboard's two BIOS chips. These are not all of the control elements the Maximus IV Extreme offers. Some more can be found on the back panel, but we want to tell you about the LED indicators first. Apart from the POST indicator, you can quickly diagnose startup-related problems with the Q-LED indicators. They go on one by one during the boot-up process: the CPU indicator goes first, next goes the memory indicator, it is followed by the graphics card one, and finally, the boot device indicator turns on. This helps you instantly identify the source of the problem. There are also Voltiminder LEDs which report the CPU, memory and chipset voltages by changing color from blue (at the default voltage levels) to yellow (at increased voltage) and red (extremely high voltage). The mainboard also has indicators of disk activity, the BIOS chip currently in use, and MemOK! and Go features. The Republic of Gamers badge on the central heatsink is highlighted just for the sake of aesthetics. You can disable all or some of the highlighting in the mainboard's BIOS.
Besides the two SATA 6 Gbit/s and four SATA 3 Gbit/s ports provided by the P67 Express chipset, there is an additional Marvell 88SE9182 controller that services two more SATA 6 Gbit/s ports. This controller uses PCI Express x4 bus and therefore offers higher peak bandwidth/performance when compared to standard x1 implementations (like the 9120 or 92128).
Each of the SATA 6 Gbit/s connectors is red and no different from another, which may provoke some confusion. Fortunately, you won’t confuse them with the SATA 3 Gbit/s connectors which are black. Besides, there is a JMicron JMB362 controller that is responsible for the two back-panel eSATA ports.
Here is a full list of the mainboard’s back-panel components:
- PS/2 connector for keyboard or mouse;
- Eight USB 3.0 ports (blue connectors) implemented via two Renesas (NEC) D720200F1 controllers and two VIA VL810 hubs, there is one more onboard pin-connector for for two more USB 3.0 ports;
- Clear CMOS button;
- Optical S/PDIF and six analogue audio-jacks provided by eight-channel Realtek ALC889 codec;
- Two eSATA 3 Gbps ports implemented via JMicron JMB362 controller;
- Bluetooth V2.1 + EDR module and RC Bluetooth button on it;
- ROG Connect button;
- One USB 2.0 port, eight more can be connected to four onboard pin-headers;
- Two local network ports (network adapters are built on Gigabit Intel WG82579 and Intel WG82583V controllers).
There is only one USB 2.0 port on the mainboard's back panel. Besides its direct purpose, you can use it for restoring or updating your BIOS by plugging in a USB flash drive with a BIOS file and pressing the ROG Connect button for a couple of seconds. The computer has to be turned off but not disconnected from the mains during this procedure. It is truly remarkable, but the reflashing doesn't even use the CPU or the system memlry. Everything happens on a "bare" mainboard. It is a very conveneint function, which may save the day if you can't start your system because the BIOS you reflashed and the processor in your configuration are incompatible. This feature is referred to as USB BIOS Flashback.
The Maximus IV Extreme has as many as eight 4-pin fan connectors, each of which is controllable. The CPU fan and three system fans can be regulated automatically by choosing one of the three available modes: Standard, Silent and Turbo. You can also set these fans up manually. The PWR fan can be set to a certain speed whereas the speed of the three OPT fans can be set to change depending on the sensors included into the mainboard box.
Take note that the numerous additional components required more room than usual, so the mainboard is larger than the standard ATX dimensions. Fortunately, it is only large in width but not in length, so it is still going to be compatible with most system cases.