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DFI LanParty JR 790GX-M3H5 mATX Motherboard

The DFI LANParty JR 790GX-M3H5 is a mATX AM3 motherboard utilizing the AMD 790GX chipset. DFI is known for the high level of BIOS controls to satisfy overclockers, but it’s also an asset for silent PC enthusiasts.

June 28, 2009 by Lawrence Lee

Product DFI LP JR 790GX-M3H5
AMD AM3 mATX Motherboard
Manufacturer DFI
Street Price US$140~$150

To many, with the demise of ABIT, DFI has become the undisputed king of enthusiast
motherboards. DFI boards typically overclock well, offer nifty
features and assertive style. The “LANParty” moniker used for their
current desktop boards perhaps most aptly applies to the LANParty JR 790GX-M3H5.
It is a mATX motherboard utilizing the AMD 790GX chipset, so it can be run without
a graphics card, but it also sports two full-sized PCI Express slots to utilize
dual graphics cards in CrossFire. Gamers who lug their systems frequently to
LAN parties would most appreciate the promise of a small, yet potent gaming
system. The high level
of customization the board provides may also be a boon for those interested
in silent computing.

Typically colorful retail box.


Package contents, minus the board.

The included cables are bright yellow and UV reflective, and the IDE cable
is rounded. Also included are a CrossFire bridge and the DFI equivalent of Asus’
Q-Connector kit which eases the task of wiring the front panel and USB headers.

DFI LP JR 790GX-M3H5: Specifications (from the
product web page
CPU * AMD® Phenom™ II
* HyperTransport 3.0 (5200MT/s) HyperTransport 1.0 (2000/1600MT/s)
* AMD OverDrive provides tuning options using the new “Advanced Clock
Calibration” overclocking feature.
* Socket 938 AM3 45nm
Chipset * AMD chipset – Northbridge:
AMD 790GX – Southbridge: AMD SB750
System Memory * Four 240-pin DDR3 DIMM
* Supports DDR3 1600(O.C.)/1333/1066 MHz
* Delivers up to 21Gb/s bandwidth at 1333MHz
* Supports dual channel (128-bit wide) memory interface
* Supports non-ECC unbuffered DIMMs
* Supports up to 16GB system memory Windows® 32-bit operating system
is unable to accurately detect more than 4GB system memory. Therefore, if
you are using this operating system, we strongly recommend that you install
a less than 3GB system memory.
Expansion Slots * 2 PCI Express (Gen 2)
x16 slots – Hybrid CrossFireXTM – combination of the integrated graphics
and a discrete graphics card in a PCIE slot (8-lane port). – Two graphics
cards support CrossFireXTM; each operating at x8 (8-lane ports) bandwidth
* 1 PCI Express x1 slot
* 1 PCI slot
* CMOS Reloaded
* CPU/DRAM overclocking
* CPU/DRAM/Chipset overvoltage
* 8Mbit SPI flash memory
Graphics * Integrated ATI Radeon™
HD 3300 graphics core
* Onboard graphics interface – HDMI port for both digital audio and video
HD display – DVI-I port for digital LCD display
* Microsoft® DirectX 10
* Hybrid CrossFireX™ technology combines the onboard GPU and a discrete
PCIE graphics card
* Onboard Performance cache for added performance
Audio * Realtek ALC885 8-channel
HD Audio Codec
* High-performance DACs with 106dB dynamic range (A-Weight), ADCs with 101dB
dynamic range (A-Weight)
LAN * Marvell 88E8056 PCIE
Gigabit LAN controllers
* Fully compliant to IEEE 802.3 (10BASE-T), 802.3u (100BASE-TX) and 802.3ab
(1000BASE-T) standards
Serial ATA with RAID * Supports up to 6 SATA
* SATA speed up to 3Gb/s
* RAID 0/1/0+1(10)/5/JBOD/AHCI
IDE * One IDE connector allows
connecting up to two UltraDMA 133Mbps hard drives
Rear Panel I/O * 1 mini-DIN-6 PS/2 mouse
* 1 mini-DIN-6 PS/2 keyboard port
* 1 HDMI-out port
* 1 coaxial RCA S/PDIF-out port
* 1 optical S/PDIF-out port
* 1 DVI-I port
* 4 USB 2.0/1.1 ports
* 1 RJ45 LAN port
* Center/subwoofer, rear R/L and side R/L jacks
* Line-in, line-out (front R/L) and mic-in jacks
Internal I/O * 4 connectors for 8 additional
external USB 2.0 ports
* 1 connector for an external COM port
* 1 front audio connector
* 1 CD-in connector
* 1 IrDA connector
* 1 CIR connector
* 6 Serial ATA connectors
* 1 40-pin IDE connector
* 1 floppy connector
* 1 24-pin ATX power connector
* 1 8-pin 12V power connector
* 1 4-pin 5V/12V power connector (FDD type)
* 1 front panel connector
* 6 fan connectors
* EZ touch switches (power switch and reset switch)
Power Management * ACPI and OS Directed
Power Management
* ACPI STR (Suspend to RAM) function
* Wake-On-PS/2 Keyboard/Mouse
* Wake-On-USB Keyboard/Mouse
* Wake-On-Ring
* Wake-On-LAN
* RTC timer to power-on the system
* AC power failure recovery
Hardware Monitor * Monitors CPU/system/chipset
* Monitors 12V/5V/3.3V/Vcore/Vbat/5Vsb/Vdimm/Vchip voltages
* Monitors the speed of the cooling fans
* CPU Overheat Protection function monitors CPU temperature during system
PCB * microATX form factor
* 24.5cm (9.64”) x 24.5cm (9.64”)


A board’s layout is important in several regards. The positioning of components
can dictate compatibility with other products (third party heatsinks mainly)
and also ease of installation. Poorly placed power connectors can also disrupt
airflow and make the system more thermally challenging.

The board is littered with yellow connectors, all UV reactive like the
included cables. Some of the board’s connectors are difficult to access:
the floppy port at the bottom of the board, the USB headers between the
two PCI-E 16x slots and two fan headers above and below the PCI-E 1x slot.
There are four more fan headers (a total of six): one PWM header at the
top of the board and three more close to the bottom right-hand corner.


The VRMs are covered with an impressive looking heatsink connected
to the Northbridge cooler via a single heatpipe. The Northbridge heatsink is very
small compared to those on other motherboards — it is jammed in an unusual position.
The Northbridge and VRM heatsinks are 36 and 35 mm tall respectively (measured
from the PCB surface). Just above the top PCI Express slot is an auxiliary
power connector to provide extra system stability when two video cards
are used.


Next to the Southbridge heatsink are a few features that make DFI stand
out. Power and reset buttons are built directly onto the board for those
who test and/or use their system without a case. There is also a diagnostic
LED so if something goes wrong you can look up the code displayed rather
than blindly swapping out parts and re-checking connections. To accomodate
extra long graphics cards, the SATA ports are placed neatly on their sides,
eliminating a potential point of interference.


The back panel includes HDMI and DVI ports as well as both optical and
coaxial S/PDIF outputs. The board lacks FireWire and eSATA. The latter, however, is not a serious lack, as eSATA is simply SATA with a different connector; a simple adapter SATA cable w/ captive PCI cover port is all that’s needed for eSATA. Still, not having it integrated on the back panel is a bit of a surprise for an enthusiast board.


The Northbridge’s proximity to the CPU socket and the height of its heatsink
may get in the way of some third party coolers like the Arctic Cooling
Alpine 64 pictured above.


Most tower heatsinks like the Xigmatek HDT-SD964 are tall enough to clear
the Northbridge, though 120mm models that can only be mounted in the north-south
orientation won’t fit if DDR3 modules with tall heatspreaders are installed
in the first two memory slots.


For enthusiasts, the options available within the BIOS can make
a board good or great. The ability to manipulate frequencies, voltages,
and fan control settings vary depending on the hardware and the amount of
trust placed in the user’s hands by the manufacturer.

“Genie BIOS” menu. Plenty of frequency and voltage options
with good ranges are available.


“Genie BIOS” menu, continued.


“PC Health Status.” The board’s fan control system can be
tweaked through three different on/off temperatures.


BIOS Summary
CPU Frequency
200 MHz to 700 MHz
CPU Voltage -800mV to +775mV in 25mV increments
Memory Frequency
800, 1066, 1333, 1600 MHz
Memory Timing Control
Memory Voltage
1.500V to 2.493V (1.612V default) in 0.0225V


NB HT Voltage
1.20V to 1.55V (1.20V default) in 0.05V
NB Core Voltage
1.15V to 1.50V (1.40V default) in 0.05V
NB PCIE Voltage
1.10V (default), 1.20V, 1.30V, 1.40V
SB PLL Voltage 1.16V (default), 1.26V, 1.36V, 1.46V
Integrated Graphics
IGX Engine Clock
150 MHz to 1000 MHz (700 MHz default)
Memory Options UMA, UMA+SidePort
UMA Frame Buffer
32MB, 64MB, 128MB, 256MB, 512MB
SidePort Clock Speed 400 MHz, 533 MHz, 667 MHz
Side Port Voltage 1.60V (default), 1.70V, 1.80V, 1.90V
Fan Control
Shutdown Temp 60°C to 90°C in 5°C increments
CPU Fan Fully On/Turn Off Temp 25°C to 50°C in 5°C increments
SYS Fan Fully On/Turn Off Temp
NB Fan Fully On/Turn Off Temp

The BIOS allows for plenty of voltage and frequency modification
to satisfy overclockers. The CPU voltage can also be decreased by up to 0.800V
and undervolting can be used with Cool’n’Quiet enabled meaning an undervolt
can be applied to both the idle and load voltage. The fan control also looks
promising — there minimum and maximum temperatures can be used to adjust
the fan behavior of three different fans.


Test Setup:

CPU-Z screenshot: Phenom II X3 720 Black Edition.


System device listing.

Measurement and Analysis Tools

  • CPU-Z
    to monitor CPU frequency and voltage.
  • CPUBurn

    processor stress software.
  • Prime95
    processor stress software.
  • FurMark
    stability test to stress the integrated GPU.
  • Cyberlink
    to play video.
  • SpeedFan
    to monitor temperature and fan speeds.
  • Seasonic
    Power Angel
    AC power meter, used to measure the power consumption
    of the system.
  • Custom-built, four-channel variable DC power supply, used to regulate
    the CPU fan speed.

Our main test procedure is designed to determine the overall system power consumption
at various states (measured using a Seasonic Power Angel). To stress CPUs we
use either Prime95 (large FFTs setting) or CPUBurn K7 depending on which produces
higher system power consumption. To stress the IGP, we use FurMark, an OpenGL
benchmarking and stability testing utility. Power consumption during playback
of high definition video is also recorded.

Cool’n’Quiet was enabled (unless otherwise noted). The following features/services
were disabled during testing to prevent spikes in CPU/HDD usage that are typical
of fresh Vista installations:

  • Windows Sidebar
  • Indexing
  • Superfetch

Video Test Suite

1080p | 24fps | ~10mbps
Rush Hour 3 Trailer 1
is a H.264 encoded clip inside an Apple
Quicktime container.


1080p | 24fps | ~8mbps
Coral Reef Adventure Trailer
is encoded in VC-1 using the
WMV3 codec commonly recognized by the “WMV-HD” moniker.


1080p | 24fps | ~19mbps
VC-1: Drag Race is a recording of a scene from
network television re-encoded with TMPGEnc using the WVC1 codec, a
more demanding VC-1 codec.


1080p | 24fps | ~33mbps
Blu-ray: Disturbia is a short section of the
Blu-ray version of Disturbia, the motion picture, played directly
off the Blu-ray disc. It is encoded with H.264/AVC.


Our test system features a Phenom II X3 720 Black Edition and a Xigmatek HDT
CPU cooler with its fan connected to a variable DC fan controller so the fan’s
power draw does not come into play. The rest of the system consists of two sticks
of Corsair Dominator DDR3 memory running at 1333MHz (9-9-9-24) in dual channel,
an Asus Blu-ray drive, a 5400RPM notebook hard drive and an OEM Seasonic 400W
power supply. 128MB of system memory was assigned to the IGP in addition to
the included SidePort memory.

Power Consumption

Test Results
Test State
Rush Hour
Coral Reef
Drag Race
(Blu-ray H.264)
CPU Load

Compared to the M4A78T-E,
an Asus ATX motherboard using the same chipset 790GX chipset, the 790GX-M3H5
uses the same amount of power when idle, and marginally more (2~4W) during video playback.
When the CPU and/or IGP were put on full load though, the DFI board used 10-14W
more power.


Lower cost boards ship with simple heatsinks on the Northbridge and Southbridge
while those targeted at enthusiasts typically have large heatpipe coolers and
heatsinks on the voltage regulation modules near the CPU socket. A well-cooled
motherboard can deliver better power efficiency and stability.

Heatsink Temperatures
Measuring Point
SB Heatsink
NB Heatsink
Measured with a spot thermometer (hottest point) after
10 minutes of full CPU + GPU load. CPU fan reduced to 8V.

The 790GX-M3H5 ran hotter across the board than the Asus M4A78T-E. While the Northbridge heatsink
measured only 1°C higher than the M4A78T-E, the Southbridge cooler was 10°C
higher and the VRM heatsink ran 17°C hotter. The Northbridge and VRM heatsink
temperatures were close due to the heatpipe distributing the heat between them. Combined,
they ran hotter than on the Asus, due probably to the VRM heatsink’s tightly spaced fins and the Northbridge
heatsink’s small size. Typically as temperature increases, electrical
components become less efficient — this could account for the 790GX-M3H5’s
higher power consumption. (Editor’s Note: Other factors such as case airflow in the system can have significant effects on all of these temperatures.)

Fan Control

To test the board’s fan control, we connected the CPU fan to a manual fan speed
controller so we could slow it down to induce higher CPU temperatures during
load. A Scythe DFS922512M-PWM (200 to 2500 RPM) fan was connected to the CPU
fan header. In the BIOS, “CPU Fan Turn Off” was set to 25C, “CPU
Fan Fully On” to 50C and “Shutdown Temperature” to 80C.

When the CPU temperature was in between the Off/Full On temperatures, the CPU
fan speed stayed fairly slow — it increased from 200 RPM at 25°C to
only 600 RPM at 50°C. Once the “Fully On” temperature was reached,
the fan speed increased almost linearly with the CPU temperature, but did not
hit the fan’s maximum speed until 75°C. At 78°C, the system shutdown.
If anything we would say the board’s fan control reacts too slowly as it did
not reach maximum speed until the Shutdown temperature was almost reached. The
“Fully On” setting acts as the trigger temperature and we suggest
you set this fairly low.

Also it should be noted that the each fan header is tied to a different temperature.
Of the two auxiliary fans that can be controlled, one is tied to the System
temperature, while the other reacts to the Chipset temperature.

SpeedFan Support

For Windows users, SpeedFan is our application of choice for fan control. It
can be configured to raise or lower multiple fan speeds to designated limits
when any specified temperature threshold is breached.

SpeedFan with correlations entered.

SpeedFan reported the fan speeds of three of the six onboard fan headers as
well as the CPU, System and Chipset temperatures (correlated to DFI’s Smart
Guardian utility). Through thermal testing we concluded that the System and
Chipset temperatures refer to the Northbridge and Southbridge. One of the temperature
sensors could not be identified — it stayed between 24C and 26C throughout

SpeedFan can control the CPU fan header (only if a PWM fan is connected) and
the System and 3rd fan headers which are the two at the very bottom of the board,
close to the onboard power/reset switches. To enable full fan control, select
the “IT8712F-J” chip in the Advanced tab of the Configuration menu
and set all the PWM modes to “Software Controlled.”

Smart Guardian

Smart Guardian: Main display.

DFI’s Smart Guardian utility provides extra information including detailed
voltage readings.

Smart Guardian: Option menu.

Smart Guardian also lets you tweak the board’s automatic fan control to suit
your inidividual preferences.


The LANParty JR 790GX-M3H5 is a classic example of what DFI is all about.
Everything about the board caters to enthusiasts, primarily those interested
in overclocking. Luckily, most of these features also appeal to those looking to
build small, quiet PCs as well. DFI’s BIOS effectively gives users free reign
to attempt high overclocks, but also ultra low undervolts. The board has a whopping
six fan headers, three of which can be controlled and customized in the BIOS,
using DFI’s own Smart Guardian utility, or with our own personal favorite application,
SpeedFan. The board also has temperature sensors for the Northbridge and Southbridge
chips so users can keep an eye out on the thermal conditions at two different
spots. Most motherboards have a single “System” or “Motherboard”
sensor but it often doesn’t correlate to a specific location or chip on the
PCB. The diagnostic LED makes it easy to diagnose problems when they arise and
the onboard power/reset switches are a nice touch — the level of consideration
DFI put into the board’s usability is difficult to match.

The board isn’t the most efficient — the 790GX-M3H5 used 10-14W more when
the CPU/IGP were stressed compared to the Asus
. This is probably related to the high temperatures we recorded
on the board’s various heatsinks. The Northbridge’s awkward location near the
corner of the CPU socket may also cause problems for some third party heatsinks,
though all the big tower coolers will fit without difficulty. Cooling will be
more challenging with two graphics cards in CrossFire mode, especially if the cards used are
of the dual-slot variety, as only one slot separates the two PCIe X16 slots. Needless to say, such a configuration running in a
mATX case will be difficult to run quietly.

at US$140~$150, the 790GX-M3H5 is one of the most expensive AM3 boards in the North American
market and it lacks a few features (like eSATA and FireWire) that are present on some
less expensive models. In reality, it is the only mATX AM3 board in wide distribution,
and all the extra touches make it a real treat to use.


* Great fan control for 3 of 6 fans
* Excellent BIOS undervolting options
* NB & SB temperature sensors
* Diagnostic LED
* Onboard power/reset switches


* High power consumption on load
* Small NB cooler
* Awkward position of NB chip
* No eSATA or Firewire

Our thanks to DFI
for the motherboard sample.

* * *

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* * *

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