Review: ASRock H97M Pro4 Mainboard

This article about the ASRock H97M Pro4 mainboard will summarize some information and test results I collected, including AC and DC power consumption figures. Please note this is not a classical review but more a test report focused on system efficiency.

Article Overview



A high-resolution photo of the H97M Pro4 can be found here.

The first image of the following shots is a side-by-side picture with the B85M-ITX on which I have done a seperate review.

The thermal image was made in idle state. Please note that some metal surfaces that seem like hotspots just reflect thermal radiation from the environment.

There are quite a lot of heat sources on the board, which will cost efficiency as we will see later on:

  • RS232 transceiver (top left corner, serial port disabled in UEFI)
  • Super-I/O (top left, above left PCIe header)
  • PCI-PCIe bridge (top left, above right PCI header)
  • Audio CODEC (top middle, above right PCIe header)
  • CPU VREG cooler (top right, above CPU cooler)
  • CPU VREG controller (mid right, besides CPU cooler)
  • RAM/PCH VREG controller (above RAM headers on the right)
  • RAM/PCH VREG inductor (bottom right, below RAM headers)
  • PCH 1.05V linear VREG MOSFET (above RAM headers on the left)
  • PCH heatsink (bottom left)
  • PCH 1.50V linear VREG (bottom left, below PCI headers)
  • PCH/LAN 3.3V standby linear VREG (left above chipset heatsink)

I’m going to remove some unused components from the board and measure the difference in power consumption. I will post another article about this.


Component Inspection

This table summarizes the components used on the H97M Pro4 as far as I was able to identify them. Please leave a comment if you can add something.

# Manufacturer Name Description Remarks
1 Intel H97 Chipset (PCH)
2 Intel I218V LAN Controller
3 Realtek ALC892 Audio CODEC
4 Nuvoton NCT6776D Super I/O
5 ASMedia ASM1083 PCI-PCIe bridge
6 TI GD75232 RS232 Transceiver
7 Intersil ISL95820 CPU VREG PWM Controller
Sinopower SM4336NSKP CPU VREG Power MOSFETs
8 Anpec APW8720B RAM/PCH VREG Controller
TI CSD87588N RAM/PCH VREG Halfbridge 2x in parallel
9 Richtek RT9045 DDR RAM Bus Terminator linear regulator
10 APEC AP9T16GH PCH 1.05V Supply Series MOSFET linear regulator
11 ?? ?? PCH 1.05VSB VREG marking: 29 1B L25
12 Richtek RT9045 PCH 1.5V VREG linear regulator
13 ?? 1117A LAN/PCH 3.3V Standby VREG linear regulator
14 APEC AP9T16GH ASM1083 1.2V Supply Series MOSFET linear regulator
15 BCD/Diodes AS358M Opamp
16 Nuvoton NCT3941S Linear Fan Controller 2x, for 3-pin fans
17 BIOS Chip


Circuit Analysis

I tried to reverse engineer some portions of the onboard power supply circuitry. This helps to understand power saving potential discussed in a seperate article.
The components in the circuit diagram are placed similar to the board layout.


Test Setup

H97M Pro4 Test Setup (including hardware, driver, software and UEFI configuration)

Component Description Price
Mainboard ASRock H97M Pro4 $80 / 80€
CPU Intel Celeron G1840 $50 / 40€
Cooler Intel boxed
RAM Crucial DDR3-1600 4GB CL11 $45 / 40€
SSD SanDisk SDSSDP-064G-G25 $60 / 40€
Input Device Logitech Unifying Receiver $8 / 10€
PSU LC-Power LC75ITX $45 / 35€


AC Power Consumption

Measurements include the AC-DC power supply, DC-DC converter (both LC-Power LC75ITX), mainboard and SSD. Absolute values include Logitech Unifying receiver, active HDMI (FullHD resolution) and Intel boxed CPU fan, but were measured with LAN cable removed and audio disabled in the UEFI.

AC Power
Power off (Deep Sleep) 0.3
Power off (WOL enabled) 0.6
Standby 1.8
Prime95 ≈ 37.0
Idle 9.3
Relative to Idle
– Unifying -0.4
– Monitor -1.2
– CPU fan -0.4
+ LAN cable +0.8
+ Audio +0.4
Power meter: Profitec KD 302 All values in Watt [W]


DC Power Consumption

All DC measurements include the mainboard only (SSD is excluded). Absolute values include Logitech Unifying receiver, active HDMI (FullHD resolution) and Intel boxed CPU fan, but were measured with LAN cable removed and audio disabled in the UEFI.

Total 12VP4 3.3V 5V 12V -12V 5VSB
Power off 0.3 0.00 0.00 0.00 0.00 0.00 0.28
Prime95 30.5 22.77 0.88 4.14 2.02 0.12 0.61
Idle 6.5 1.92 0.88 1.84 1.15 0.12 0.61
Relative to Idle
– Unifying -0.4 -0.13 -0.26
– Monitor -1.0 -0.77 -0.10 -0.15
– CPU fan -0.4 -0.36
– HDMI cable 0.0
+ LAN cable +0.6 +0.03 +0.60
+ Audio +0.3 +0.27
All values in Watt [W]


CPU Power States

For a low idle power consumption of the whole setup, it is essential for the CPU to reach both C6 power state for both the core and the package. To make this possible, the right combination of hardware, BIOS settings and device drivers has to be used. Refer to the test setup PDF for details.

In my setup, the H97M Pro4 reached C6 CPU core and package power states without any hassles as confirmed by ThrottleStop. The higher C7 state is not supported by the Intel Celeron CPU that was used for the tests. The computer does run stable without any issues so far.

Some further remarks:

  • When the CPU enters package C6, the mainboard will produce a silent chirp noise independent from the used power supply.
  • With plugged-in LAN cable interrupts cause the CPU to leave package state C6 more often.
  • The “H97M Pro4” is just a sticker on the board. There is a “Z97M Pro4” underneath, so the same PCB is used for both mainboards.


LAN Performance

The onboard LAN controller is an active solution (Intel I218V). CPU utilization during network transfers is very low compared to a passive controller like that one used on the B85M-ITX.

The following data is recorded for a large file transfer over SMB. CPU utilization is measured with Process Explorer.

Transmitting Receiving
Speed 112 MB/s not measured
CPU total utilization 19%
CPU interrupt utilization 8%


Further reading


2 thoughts on “Review: ASRock H97M Pro4 Mainboard

  1. Love this teardown / review / circuit analysis, the world needs more of these. Looking forward to component removal power tests.

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