The PCB and connectors:
The tools for clocking:
Let’s start with the elements inserted on the PCB which can be interesting tools for overclockers. There are a lot of them on this model, which has become a habit with Asus on the high end. This confirms its position as a card dedicated to overclocking.
- The power button: allows the powering of the motherboard.
- The FlexKEY (reset ) : allows to restart the motherboard in case of failure. The button can now be assigned to another task via the BIOS.
- Safe Boot: allows to restart the board even if the parameters chosen in the bios do not allow the boot. This avoids having to do a CMOS Clear to reboot and thus lose your encoded settings.
- ReTry Button : during cold tests, sometimes the OS freezes and a reset doesn’t allow to restart the motherboard : only solution 6, 7 seconds by keeping the START button pressed. With the ReTry button, it restarts immediately.
- Switch bios : allows to switch between the two bios. You can choose to have an ” overclocking ” bios and a more stable bios for a H24 configuration.
- Slow Mode: allows you to boot with a 16x coefficient and once in the OS to put back the one chosen in the bios. It is especially for max screens.
- RSVD: when activated under cold conditions (-120°C), it avoids ” Cold boot bug “.
- LN2 Mode : allows to activate LN2 profiles in the bios.
- The debug LED: 4 diodes (CPU – DRAM – VGA – BOOT) which allow to diagnose errors during the boot of the board. If one of them stays on, it means that the corresponding component has a problem.
- The Q-Led: allows to display a code corresponding to the component responsible for the error during the boot.
- The CMOS CLR: allows to erase the BIOS parameters in order to return to the default ones.
- ProbeIT : allows to measure voltages with a multimeter directly on the PCB.
A little extra for cold tests:
In addition to all these tools, the board has three probes on the back of the PCB that will be able to detect condensation during liquid nitrogen testing:
- Processor: flashes when condensation is detected near the CPU.
- DRAM: flashes when condensation is detected near the DRAM.
- PCIe: flashes when condensation is detected near the PCIe.
PCB:
Our Asus Maximus Z690 APEX is based on a 24 + 2 phase power supply. The part in charge of the CPU consists of 24 phases and on this model, no doubler, but beware the phases are placed in parallel: they are really 12. The controller is a RAA229131 chip(X+Y=20) on which we are trying to get more information.
The 24 mosfets are all RAA 22010540 of 105A grouped in parallel by phase and thus allow to split them without using a doubler. The mosfets in the power stages generate the most heat because they are responsible for the voltage conversion and delivery to the CPU from the 12 volt EPS connector.
Connectors:
The rear panel has the following components. First of all the Clear CMOS as well as the button for flashing the bios from a USB stick. One of the particularities of the card is to have two PS/2 slots to connect a keyboard and a mouse. But why still use this type of connector in 2021? Simply because some benchmarks are more powerful under XP (Super Pi) and the use of non-USB peripherals greatly facilitates the installation of the OS.
In terms of USB ports, this ROG Maximus Z690 APEX has four USB 3.2 Gen 1, five USB 3.2 Gen 2 and one USB 3.2 Gen 2 Type-C. Then we find the antenna supports for dual band Wi-Fi. The audio part is provided by a SupremeFX ALC4080 chip. Finally, we find the various audio outputs and network ports (2.5G).
