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Asus M3A78 Pro: An ATX 780G Motherboard

The AMD 790G chipset is here now, and a board review is underway, but in the meanwhile, we thought it would interesting to revisit the previous generation AMD chipset. The Asus M3A78 Pro is an ATX board based on AMD’s 780G chipset, widely applauded as possibly the best to date. Has it changed much since the intro in early spring?

August 6, 2008 by Lawrence Lee

Product Asus M3A78 Pro
AM2/AM2+ Motherboard
Manufacturer ASUSTeK
Street Price US$110

If you read the title of the review and wondered whether we already reviewed
the Asus M3A78 Pro, you’re probably not alone. Despite all the good products
that Asus has produced over the years, they, as well as scores of other companies,
fail in one simple criteria: nomenclature. The M3A78 Pro is an
ATX board based on AMD’s 780G chipset. That makes enough sense. The M3N78
, which we reviewed recently, is an ATX board featuring nVidia’s Geforce
8300 chipset. That doesn’t make much sense; why not M3N830 Pro?

The two boards appear to have the exact same feature set, with only the chipset
differentiating them. This provides an unique opportunity — assuming that
Asus did not favor one chipset over the other in their implementation, this
is as close as it gets to direct chipset comparison with actual retail products.
And it’s a worthy comparison considering the chipsets in question. When 780G
was released, it was a milestone for IGP’s — providing full high definition
video offloading and far superior gaming performance in the form of the Gigabyte
we reviewed in the spring. And now after a few months, it’s
had time to mature. The Geforce 8300 impressed us quite a bit, too. While the
Asus M3N78 Pro lacked high 3D performance, it compensated by being extremely
proficient in all other areas. We found the M3N78 Pro to be an efficient motherboard
that worked very well straight out of the box no real issues, a rarity these

The M3A78 Pro box with its semi-reflective green coating is almost identical
to the M3N78 Pro. This should be interesting.


The accessories: IDE, floppy and SATA cables, SATA power adapters, HDMI-DVI
adapter, manual, support disc, I/O shield and Q-Connector kit.


Asus M3A78 Pro: Specifications (from the
product web page
AMD Socket AM2+ / AM2 Processors
AMD Phenom™ FX / Phenom / Athlon™ / Sempron™
AMD Cool’n’Quiet™ Technology
Support CPU up to 140W
Chipset AMD 780G/SB700
System Bus Up to 5200/MT/s ; HyperTransport™
3.0 interface for AM2+ CPU
2000 / 1600 MT/s for AM2 CPU
Memory 4 x DIMM, Max. 8 GB, DDR2
1066/800/667 ECC,Non-ECC,Un-buffered Memory
Dual Channel memory architecture
*Due to AMD CPU limitation, DDR2 1066 is supported by AM2+ CPU for one DIMM
per channel only.
**Please refer to www.asus.com or user manual for Memory QVL(Quality Vender
***When installing total memory of 4GB capacity or more, Windows® 32-bit
operation system may only recognize less than 3GB. Hence, a total installed
memory of less than 3GB is recommended.
Expansion Slots 1 x PCIe x16 (Support PCIe
2.0 / 1.0 Architecture )
2 x PCIe x1
3 x PCI 2.2
CrossFire Hybrid CrossFireX™
Support (For Windows Vista only)
VGA Integrated ATI Radeon™
HD 3200 GPU
Supports HDMI™ Technology with max. resolution up to 1920 x 1200 (1080P)
Supports DVI with max. resolution up to 1600×1200 @60Hz
Supports D-Sub with max. resolution up to 2560×1440 @ 75Hz
Hybrid CrossFireX™ Support (For Windows Vista only)
Supports Microsoft® DirectX 10, OpenGL 2.0, Pixel Shader 4.0
Maximum shared memory of 256MB
Storage Southbridge
1 xUltraDMA 133/100
6 xSATA 3 Gb/s ports
Support RAID 0,1,10
LAN Gigabit LAN
Audio Realtek® ALC1200 8 -Channel
High Definition Audio CODEC
-Coaxial S/PDIF out port at back I/O
USB 12 USB 2.0 ports
ASUS AI Lifestyle Features ASUS Express Gate
– Web browser, file downloading and uploading*
– Further free features upgradable
* File downloading and uploading through USB devices only
ASUS Quiet Thermal Solution
– ASUS AI Gear 2
– ASUS Q-Fan 2
– 4+1 Phases ASUS Power Design
ASUS Crystal Sound
– ASUS Noise Filter
– ASUS Q-Connector
– ASUS Q-Shield
– ASUS O.C. Profile
– ASUS EZ Flash 2
Overclocking Features Intelligent overclocking
– AI Overclocking (intelligent CPU frequency tuner)
– ASUS AI Booster Utility
Precision Tweaker
– vDIMM: 8 -step DRAM voltage control
– vCore: Adjustable CPU voltage at 0.0125V increment
– vChipset 4-step Chipset voltage control
SFS (Stepless Frequency Selection)
– FSB tuning from 200MHz to 600MHz at 1MHz increment
– Memory tuning from 533MHz up to 1066MHz
– PCI Express frequency tuning from 100MHz up to 1066MHz at 1MHz increment
Overclocking Protection
– ASUS C.P.R.(CPU Parameter Recall)
Special Features ASUS MyLogo 2
Uses 100% All High-quality Conductive Polymer Capacitors!
Back Panel I/O Ports
1 x D-Sub
1 x PS/2 Keyboard
1 x HDMI
1 x PS/2 Mouse
1 x S/PDIF Out (Coaxial)
1 x LAN(RJ45) port
4 x USB 2.0/1.1
8 -Channel Audio I/O
Internal I/O Connectors 4 x USB connectors supports
additional 8 USB 2.0 ports
1 x Floppy disk drive connector
1 x IDE connector
6 x SATA connectors
1 x CPU Fan connector
1 x Chassis Fan connector
1 x Power Fan connector
1 x 4-pin ATX 12V Power connector
1 x S/PDIF Out connector
24-pin ATX Power connector
Front panel audio connector
COM connector
Chassis Intrusion connector
CD/AUX audio in
System Panel
BIOS 8 Mb Flash ROM
DMI 2.0
WfM 2.0
ACPI 2.0a
ASUS EZ Flash 2
Accessories UltraDMA 133/100/66 cable
FDD cable
SATA cables
SATA power cables
1 x HDMI to DVI Convertor
User’s manual
2 in 1 Q-connector
Support Disc Drivers
Express Gate
ASUS Update
Anti-virus software (OEM version)
Form Factor ATX Form Factor
12 inch x 9.6 inch ( 30.5 cm x 24.4 cm )


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 airflow
and make the system more thermally challenging.

Bird’s eye view.

At first glance, the layout appears to be rather pedestrian. Clearance around
the CPU socket is a bit tight due to the close proximity of the DIMM slots.
A large CPU heatsink may make the yellow slots inaccessible. The chipset heatsink
is also close by though is probably not tall enough to cause problems. Most
of the power regulation circuitry is neatly lined up in a row near the back
panel and both power connectors are out of the way. Fan headers are strategically
placed at the top, rear and front of the board.

Viewed from the side.

From the side the board appears stream-lined due to the use of short, solid-state
capacitors. The IDE port lies on its side, helping the cumbersome IDE cable
be just a little bit less obtrusive. The SATA ports are further away from the
edge than we’d like. Ideally they’d be on their sides as well next to the IDE
connector. The floppy connector is in the worst place imaginable, at the very
bottom buried under the last PCI slot and next to the USB headers. The USB headers
and system panel are easily accessed using Asus’ Q-Connector kit, but installing
a floppy cable would be troublesome if expansion cards are present.

Chipset heatsinks.

In the center of the board sits a large northbridge heatsink held down by plastic
spring-loaded push-pins. Its fins are thick and broad, making heat dissipation
less than optimal. At 32mm high measured from the surface of the PCB, it should
not pose a problem for the majority of third party heatsinks. The ASUS nameplate
top the chipset heatsink is not likely to be helpful; such cosmetics have been
known to impede cooling. Next to the SATA ports, a smaller cooler is also present
on the southbridge. It’s a typical low-profile heatsink commonly found on Asus

Back panel connectors.

The back panel allows for various forms of connectivity. Along with the typical
analog audio, USB, and ethernet ports, Asus provides video via VGA and HDMI,
and S/PDIF via coaxial. DVI is provided via an adapter that plugs into the HDMI


BIOS options on mATX boards are typically very spartan. The
presence of an IGP and the more limited cooling associated with an mATX platform
makes manufacturers nervous about allowing users the ability to customize
their clock/voltage settings. ATX boards are usually more tweaker-friendly
and the M3A78 Pro is no exception.

“Advanced” options.

Compared to the M3N78 Pro, Asus provides a few more options
in the M3A78 Pro’s BIOS. All the typical voltage and frequency controls
you’d see on a budget enthusiast mainboard are present.

Notable Available BIOS Adjustments
CPU Frequency 200Mhz to 600Mhz in 1Mhz increments
PCI-E Frequency 100Mhz to 150Mhz in 1Mhz increments
Memory Frequency 533/667/800Mhz (may depend on CPU)
Memory Timings Various
CPU Voltage 0.8000V to 1.7000V in 0.025V increments
Memory Voltage 1.90V to 2.25V in 0.05V increments
Northbridge Voltage 1.10V to 1.40V in 0.10V increments
Video Memory Size 32MB, 64MB, 128MB, 256MB, 512MB

Wide ranges are given for CPU frequency and voltage, but memory
settings are more restricted. Unlike the M3N78, The M3A78 offers full memory
timing control for those of you who are into that kind of thing.

“Hardware Monitor.”

The Hardware Monitor section is fairly spartan. CPU and MB temperatures
are reported as well as fan speeds from all three fan headers. The Q-FAN feature
is available with three different settings: Performance, Optimal, and Silent.
There is no separate option for CPU and Chassis fans meaning one of two things:
only the CPU fan can be controlled, or all the fans that can be controlled
use the same profile.

We should also note that almost every time we changed a major
setting in the BIOS, such as voltage, frequency, or Q-FAN profile, the system
failed to POST afterwards. The system had to be powered off and on again,
which as you can imagine can be very annoying. A BIOS update failed to resolve
this issue. While it isn’t a game-breaker, it certainly be a deciding factor
if you do enjoy tweaking the BIOS frequently.


Asus Express Gate is a recently added feature that allows users
almost instant access to a web browser, photo viewer, chat client (Pidgin)
and VOIP (Skype). It is powered by Splashtop, an instant-on Linux desktop
developed by DeviceVM. Instead of waiting for up to a minute for the main
operating system to boot-up, Express Gate is available as soon as the system
POSTs. On budget models like the M3A78 and M3N78, Express Gate requires installation
on your primary hard drive (it creates a hidden folder to house itself) prior
to use. On premium models, Express Gate is available right out of the box.

The SlashTop desktop.



Test Setup:

Measurement and Analysis Tools

Our main test procedure is designed to determine the overall system power
consumption at various states (measured using a Seasonic Power Angel), and to
test the integrated graphics’ proficiency at playing back high definition videos.
Standard HD-DVD and Blu Ray discs can be encoded in three different codecs by
design: MPEG-2, H.264/AVC and VC-1. MPEG-2 has been around for a number of years
and is not demanding on modern system resources. H.264 and VC-1 encoded videos
on the other hand, due to the amount of complexity in their compression schemes,
are extremely stressful and will not play smoothly (or at all) on slower PCs,
especially with antiquated video subsystems.

We use a variety of H.264/VC-1 clips encoded for playback on the PC. The clips
are played with PowerDVD 7 and a CPU usage graph is created by the Windows Task
Manger for analysis to determine the approximate mean and peak CPU usage. High
CPU usage is indicative of poor video decoding ability on the part of the integrated
graphics subsystem. If the video (and/or audio) skips or freezes, we conclude
the board’s IGP (in conjunction with the processor) is adequate to decompress
the clip properly.

Cool’n’Quiet was enabled the following features/services were disabled during
testing to prevent spikes in CPU/HDD usage that are typical of fresh Vista installations:

  • User Access Control
  • Microsoft Defender
  • Windows Sidebar
  • Indexing
  • ReadyBoost
  • Superfetch
  • Windows Search
  • Security Center
  • Aero interface

Video Test Suite

1080p | 24fps | ~10mbps
Rush Hour 3 Trailer 1
is encoded in H.264 with Apple Quicktime.


1080p | 24fps | ~7.5mbps
Coral Reef Adventure trailer
is encoded in VC-1 using the
WMV3 codec (commonly recognized by the moniker, “HD WMV”).


720p | 60fps | ~12mbps
WVC1: Microsoft Flight Simulator X trailer
is encoded in VC-1. It is encoded using the Windows Media Video 9
Advanced Profile (aka WVC1) codec — a much more demanding implementation
of VC-1.


1920×1080 | 24fps | ~19mbps
WVC1: Drag Race is a recording of a scene from
network television re-encoded with TMPGEnc using the WVC1 codec. It
is the most demanding clip in our test suite.


Our test system is fairly basic, featuring an ODM 80Plus power supply, notebook
hard drive and Blu-ray drive. The CPU is a X2 4850e, a mid-level dual core 45W
processor. It is cooled by a stock AMD heatpipe cooler with PWM fan connected
to a variable DC fan controller (so the fan’s power draw does not come into

vs. Gigabyte GA-MA78GM-S2H

Posted in the table below are the test results for the Asus M3A78 Pro board
compared to the earlier 780G Gigabyte board we reviewed some months ago with
exactly the same system components.

Test Results: 780G vs. 780G
Test State
Asus M3A78 Pro
Gigabyte GA-MA78GM-S2H
Mean CPU Use
Peak CPU Use
System Power
Mean CPU Use
Peak CPU Use
System Power
Sleep (S3)
Rush Hour
Coral Reef
Flight Sim.
Drag Race
CPUBurn + ATITool

The power consumption at idle was similar to the Gigabyte
despite the fact that CPU-Z reported the CPU voltage to be
approximately 1.00V — a full 0.10V less than normal. Strangely when we
set the Cool-n-Quiet speed/voltage manually to 1.0Ghz/1.00V, the system only
drew only 33W when idle, so either CPU-Z was wrong, or something was preventing
CnQ from fulfilling its full potential. We ran into another quirk during playback
of the Rush Hour H.264 clip — once it began playing, CnQ became disabled,
forcing the CPU to run at 2.5Ghz when normally it would stay underclocked for
such a light task, which saw CPU load peaks of just 12%. Afterwards, Vista’s
CPU power management settings had to be reset to default to re-enable Cool-N-Quiet.

The rest of the video playback was pretty much on par except for CPU usage,
which was significantly higher on the Asus board, but this did not make its
power consumption higher than the Gigabyte. The M3A78 turned out to be much
more efficient at heavy load — measuring 15-21W lower than the MA78GM.
It is difficult to account for these differences as many factors could be at
play. Since we last tested the MA78GM, Vista Service Pack 1 came out, as well
as several sets of ATI drivers, all of which could give the Asus an unfair advantage.
To complicate matters, our MA78GM board was a very early sample, not a retail
model and a bad BIOS flash bricked the board, which meant we were unable to
retest it. And of course Asus is a completely different manufacturer, and the
M3A78 has a slightly different feature-set and form factor.

vs. Asus M3N78 Pro

Asus M3A78 Pro vs. M3N78 Pro @ 2.5Ghz
Test State
Asus M3A78 Pro
Asus M3N78 Pro
Mean CPU Use
System Power
Mean CPU Use
System Power
Sleep (S3)
Rush Hour
Coral Reef
Flight Sim.
Drag Race
CPUBurn + ATITool

Compared head to head against the Asus nVidia-based equivalent M3N78
Pro, the results were surprising. When idle and playing video, the M3N78 Pro
had an advantage in terms of power efficiency, especially when playing back
less demanding clips. CPU usage was also significantly lower, making it a better
choice for multitasking. Once heavy load was applied however, the M3A78
Pro pulled ahead dramatically, drawing 10W less power. From these results one
could deduce that nVidia’s IGP is actually more efficient, but the power regulation
is not as good at high load, resulting in high power consumption when the CPU
is pushed to its limit.

Test Results: Asus M3A78 Pro vs. M3N78 Pro @ 1.5Ghz
Test State
Asus M3A78 Pro
Asus M3N78 Pro
Mean CPU Use
Peak CPU Use
System Power
Mean CPU Use
Peak CPU Use
System Power
Rush Hour
Coral Reef
Flight Sim.
Drag Race
CPUBurn + ATITool
X2 4850e @ 1.5Ghz undervolted to 1.100V, Cool-N-Quiet

When the CPU speed was dropped to 1.5Ghz, our test setup could no longer play
the two most challenging VC1 clips in our test suite. Accompanied by high CPU
usage, the audio in the Flight Simulator video began to clip, and skipping was
evident during the Drag Race clip. The M3N78 Pro had no problems with our test
suite at 1.5Ghz. Underclocked, the M3N78 Pro was much closer to the M3A78 Pro’s
load power consumption, indicating once again that the M3N78 is “greener”
at lighter load.


When it comes to customizable control, SpeedFan is our application of choice.
If properly supported, it can be configured to raise/lower multiple fan speeds
to designated limits when any specified temperature threshold is breached.

SpeedFan vs. PC Probe.

The screenshot above shows the correlation between SpeedFan’s readings and
the temperature and fan speed sensors. Most of the readings in SpeedFan were
corroborated by Asus’ PC Probe utility. We found that SpeedFan could be configured
to control both the CPU and Chassis fan headers. Setting PWM modes 1 and 2 in
the Advanced menu from “SmartGuardian” to “Software Controlled”
enabled the speed controls. CPU and Chassis fan headers have separate controls
if a PWM fan is connected to the CPU header. If two 3-pin fans are used, they
are both controlled using Speed02.

To test the range of the controls we connected two fans to the system: a Scythe
92mm PWM and a Scythe 80mm fan. The PWM fan speed varied from 260 to 2500 RPM,
and the 3-pin fan could be fully controlled from off to 1560 RPM. Incidentally
the fans run at 2600 RPM and 1560 RPM repectively at 12V.

To test how well Q-FAN’s profiles worked, we connected the fan on the CPU cooler
to a variable DC fan controller set to a relatively low 5V and proceeded to
stress the processor using CPUBurn. The CPU and Chassis fan speeds were monitored
and graphed using SpeedFan.

CPU fan speed behavior.

The CPU fan spun at the maximum speed in “Performance” mode, regardless
of CPU temperature. In “Silent” mode, the CPU fan kick-started but
then immediately turned itself off when the POST screen appeared, resulting
in a CPU fan error prompt. It would not spin up again until the CPU temperature
reached about 60°C. . The stock AMD fan did not have this problem, however.
In “Optimal” mode, again the CPU fan did not spin up, this time waiting
until 42°C to kick in, though we did observe it beginning to twich at 40°C.

CPU fan speed behavior.

In “Performance” mode, the chassis fan always ran at full speed (1550
RPM). In “Silent” and “Optimal” mode, the fan remained at
approximately 900 RPM and then jumped quickly once temperature thresholds of
42°C and 58°C respectively prompted them to spin up.


With very effective third party heatsinks on the market, and many low power
CPUs available, overclocking can improve performance without compromising the
noise level of a silent PC. A simple overclocking investigation was conducted
with the CPU multiplier set to 5x and RAM at 533Mhz/2.10V. The CPU frequency
was increased in increments of 10Mhz until the system failed a 5 minute
run of Prime95 with ATITool 3DView running simultaneously or failed
to boot or showed other signs of instability.

The maximum FSB overclock with our X2 4850e.

We found that the M3A78 Pro was good up to a CPU frequency increase of 300Mhz.
At 310Mhz, Prime95 produced an error after only one minute. No graphical anamolies
were detected by ATITool, suggesting the overclock did not compromise the video
subsystem. With ample voltage applied to our X2 4850e processor, we managed
to get it partially stable at 3.16Ghz using a 10.5x multiplier. Our overclocking
attempts were hampered by the processor itself — we probably needed increased
cooling or extremely high CPU voltages, neither of which are silent-friendly.


We usually run 3DMark05/06 to get a sense of how suitable the board’s IGP is
for 3D gaming, but unfortunately we were not able to get the test suite to run.
The Futuremark splash screen would appear and then freeze. We tried different
driver sets and the newest BIOS but were unable to resolve this issue. We can
assume that the board performs as well as the Gigabyte GA-MA78GM-S2H given that
they use the same chipset. Below are 3DMark results of the Asus M3N78
Pro, Gigabyte GA-MA78GM-S2H, and ATI’s budget discrete video card, the Radeon
HD 3450.

Futuremark Comparison
Geforce 8300 IGP
(HD 3200 IGP)
(HD 3450)
All results with 2GB of system RAM and 256MB of VRAM
assigned (when applicable).


When we connected the board’s HDMI output to our BenQ FP94VW monitor, it allowed
us to select a large variety of resolutions including the native resolution
of 1440×900 which turned out to be the best fit. The resulting image was reduced
however with narrow black borders on all sides. The text was also distorted
(pictured above), though it may look better on a TV rather than a monitor. The
audio portion of the signal worked flawlessly.

Distorted text with HDMI.


To test how well the board’s chipset heatsinks performed, we overclocked the
CPU frequency to 300Mhz, and lowered CPU cooling fan’s voltage to 5V to reduce
the amount of top down airflow they received. After 20 minutes of stressing
the system with CPUBurn, the northbridge heatsink reached 58°C, as measured
by an infrared thermometer — hot enough that three seconds of direct skin
contact was too much to handle. The southbridge cooler on the otherhand was
pleasantly warm at 47°C. The power regulation circuitry to the left of the
CPU socket also got fairly hot, between 55°C and 60°C. At no point during
testing did we observe any instability from the board.


The Asus M3A78 Pro has a lot going for it. 780G high definition playback remains
solid, and under heavy load, the board boasts much lower power consumption than
the Gigabyte 780G board we reviewed. The M3A78 Pro allows two fans to be controlled,
though the Q-FAN profiles exhibit very primitive behavior. Luckily, in Windows,
they can be controlled via SpeedFan. For power users, it overclocks extremely
well, especially considering there is an onboard graphics chip present. Express
Gate is a simple, yet effective tool if you’re in a rush — a one minute
bootup sequence can seem like an eternity when all you want to do is check the

However, there are several unresolved issues that left us nonplussed. While
the inability to run 3DMark and a slightly distorted HDMI image we can live
with, the inability to POST following BIOS changes, and Cool-N-Quiet being disabled
in Vista when H.264 video is played are extremely annoying bugs. Individually,
they may seem like minor problems but when they coexist together, it makes us
wonder what else doesn’t work properly. All these issues arose during only a
single day of testing.

In comparison, the nVidia 8300 chipset Asus
M3N78 Pro
had only one minor HDMI issue, a slightly zoomed-in image
— everything else worked almost perfectly. It does not overclock as well,
and its power consumption is worse at high load, but in all other regards, it
is less buggy product. These issues need to be resolved, perhaps with updates
in the BIOS, before it can earn our full recommendation. The M3A78 Pro may be
the better hardware, but it’s hard to tell with so many blemishes.


* Good high definition playback
* Low power consumption especially under heavy load
* Excellent overclocker
* Express Gate convenient for simple tasks


* Several miscellaneous bugs/issues

Our thanks to Asus
for the M3A78 Pro sample.

* * *

Articles of Related Interest
Asus M3N78 Pro: Geforce 8300
& HybridPower Explored

AMD 780G: Best Ever Integrated
Mainstream Chipset?

Asus P5E-VM HDMI: A microATX
C2D board for gamers?

Intel DG33TL G33 Express chipset
mATX motherboard

Asus M2A-VM HDMI: AM2 mATX motherboard
Albatron KI690-AM2: A Mini-ITX Powerhouse

* * *

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