Earlier last month we released our review of the AsRock Z390 Phantom Gaming X (Italian), praising its features and overall quality, today we are going to analyse its VRM.
The ASRock Z390 Phantom Gaming X features a 14 phase VRM using a 6 phase (with a doubler) configuration for the Vcore + 2 phase configuration for the iGPU.
Most of the components are similar to the one present on the Z390 Phantom Gaming 7 we released a couple of weeks ago(Italian).
The Vcore controller, the ISL69318 from Intersil is a Digital Multiphase Controller configurable to support any desired phase assignments up to a maximum of seven phases across the two outputs (X and Y), here we see it using a 6+1 configuration with a total of seven ISL6617A doublers in order to achieve the 14 phases count.
The Vcore and SOC power stages are the Vishay SIC634, which are DrMOS(Driver Mosfet) being able to support a maximum amount of 50A continuous current and 55 A at 10 ms peak current, with a switching frequency up to 2MHz, the bad size is that the DrMOS do not do current and temperature monitoring, this lack is balanced by the doublers used (which incorporates current monitoring).
Let’s take a look at the efficiency and heat output of the Vcore:
| Vcore | Switching Frequency | Current | Heat |
| 1,0 V | 500 kHz | 100 A | 8 W |
| 1,0 V | 500 kHz | 150 A | 12 W |
| 1,0 V | 500 kHz | 200 A | 18 W |
| 1,0 V | 500 kHz | 250 A | 25 W |
| 1,0 V | 500 kHz | 300 A | 36 W |
| 1,0 V | 500 kHz | 400 A | 56 W |
| 1,0 V | 500 kHz | 500 A | 85 W |
| 1,0 V | 500 kHz | 600 A | 120 W |
The range 100A to 200A is the one in which an Intel I9-9900K operates on ambient cooling, considering the stock settings and the typical maximum OC possible, we can see how the total heat that will be produced will be perfectly handled by the massive cooling present on the VRM, the higher current values are usually for Liquid Nitrogen overclocking whereas the last value (600A) is the maximum amount of current that will be handled, continuously, by the Vcore.
The phases are cooled by two aluminium blocks (Super Alloy XXL) with a substantial mass and have “aerodynamic” fins to improve heat dissipation. The armour plate, located on the back of the motherboard, provides structural solidity, but no type of cooling.
