ABIT was all dressed up with no place to go with the BM6, the reason behind this being that ABIT's ultra stable, ultra overclockable BM6 was utterly wasted on one of the most unoverclockable CPU platforms Intel offers currently, the Socket-370 Celeron.  Although the 300MHz PPGA (Socket-370) Celeron apparently functions quite well as a 450MHz performer, the newer 366, 400 and upcoming 433MHz Celeron CPU's are about as overclockable as the old Cyrix 6x86 processors were, meaning that they aren't the world's best overclockers.  So with the ABIT BM6, you were essentially spending $100 on a motherboard whose features were about as useful to you as a heatsink on your BIOS chip. 

ABIT's solution?  A scaled down, albeit not crippled, version of the BM6 based on Intel's "scaled down" version of the BX chipset, the 440ZX.  Rightfully dubbed, the ZM6, ABIT is back with a motherboard that looks virtually identical to the BM6 on the outside, but marches to the beat of a different drummer on the inside with the 440ZX chipset powering the board; and above all, the ZM6 offers you just about everything the BM6 did, with one desired absence, the higher cost of a board whose potential you'll never tap.

New Anand Tech Report Card Rating
89/B+

Do not compare newer ratings to older ones, the newer ratings are much more aggressive

The Good

The ZM6 is perfectly identical, from a layout perspective, to the ABIT BM6 with the only difference being that in place of the 443BX North Bridge controller, ABIT outfitted the ZM6 with the 443ZX North Bridge chip, a difference which will be discussed shortly.  The ZM6 features ABIT's now standard 5/2/1 expansion slot configuration (PCI/ISA/AGP), and just like the BH6 and the BM6, the board features a total of three DIMM slots for memory expansion.

The physical size of the motherboard's PCB is an extremely manageable 12" x 8.3" (30.5cm x 21.0cm) which happens to be the same size as the good ol' ABIT BH6.  The HDD and FDD connectors are placed along the bottom edge of the motherboard, and the Socket-370 interface is crowded by electrolytic capacitors designed to improve the stability of the motherboard.  If you were to judge the motherboard based solely on looks, you could dismiss the ZM6 as being a BM6 look alike and calling it quits.  Fortunately, for ABIT's sake (otherwise this would be one short review) the ZM6 does offer its own set of unique qualities.

The 440ZX chipset is to the 440BX chipset as the 440EX chipset was to the 440LX chipset.  If that last statement made absolutely no sense whatsoever to you then let's work on clarifying the positioning of the 440ZX chipset.  The 440BX chipset contains a few features that some users will never use, one of which happens to be its support for up to 8 rows of memory (4 double-sided DIMMs).   If you look at a standard 16x64 128MB SDRAM DIMM you'll notice that there are physically chips on both sides of the DIMM, as you might be able to guess, that means the DIMM in question is a double-sided DIMM.  At the same time, if you look at a standard 8 x 64 64MB SDRAM DIMM you'll notice that there are chips on only one side of the DIMM, meaning that this particular DIMM would be a single-sided DIMM.  So on a motherboard with the BX chipset, you could theoretically install 8 of the single-sided 64MB DIMMs or 4 of the double-sided 128MB DIMMs.  Before you begin bragging about how you can do that on your motherboard, quietly ask yourself if you'll ever need 512MB of RAM. 

Chances are, unless you're going to be operating a high end workstation or server (in which case you should stop considering a Socket-370 Celeron as a possible processing platform), that you won't reach that 512MB memory limit anytime soon that is provided for by the BX chipset 8 addressable rows of memory.  This is the same BX chipset that is found on the ABIT BM6, now if you're not going to be using that much memory it wouldn't make much sense to be using a chipset that supports a feature you're not going to be using during the lifetime of your computer.   ABIT's solution?  The Intel 440ZX chipset, with 4 addressable rows of memory, you can install 2 double-sided DIMMs or any combination of double and single-sided DIMMs to approach that 4 row memory limitation of the ZX chipset.  Because of the numerous possibilities when installing RAM on a 440ZX based system, ABIT chose to outfit the ZM6 with three DIMM slots capable of accepting either double or single-sided DIMMs, allowing for a user to install 3 single-sided 64MB DIMMs on the ZM6 where they would only be able to install 2 on a standard ZX board with a meager two DIMM slots.  ABIT even claims that, in-lab, they have been able to exceed Intel's specified memory limitation of the ZX chipset by 256MB with two double-sided PC66 Hitachi 256MB SDRAM modules for a total of 512MB of RAM. 

The second, and final difference between the 440ZX and the 440BX chipset lies in the ZX's support for a total of 4 bus master PCI slots in comparison to the BX's support for 5.  In order to cut costs on the ZM6 (since the ZM6 is identical to the BM6 in every way except the presence of the ZX chipset, it is cheaper to build two motherboards out of a similar design that to create a new design for every board) ABIT included a 5th PCI slot without the ability to be run as a bus master PCI peripheral.  While some peripherals do require that they be installed in a PCI master slot, there are a few exceptions such as some PCI graphics accelerators (i.e. Matrox Millennium/Millennium II), 3D accelerators, and some Ethernet adaptors among other devices that don't require the presence of a PCI bus master signal in the slot they're installed in. 

Other than those two key differences, the ZM6 performed identically to the ABIT BM6 in AnandTech's performance and stability tests.   As taken from the BM6 review, the conclusion to the benefits of the ZM6 are identical to those of the BM6, including stability.

The argument has been made that bigger capacitors in greater quantities on a motherboard is not necessarily better, and the truth of the matter is, that it is not.  The entire trend of assuming that bigger is better was actually brought about by an editorial written a few years back about a well-known motherboard manufacturer in which the company was praised for having such highly rated and stable products.  In response to the question why their boards were so stable, the classic response from the company was "well, we have bigger capacitors."  A statement that was backed up by the use of larger capacitors on their motherboards, a trait that continues to be seen on their products to date.  In reality, the "praising" editorial was nothing more than an attempt to appease the motherboard manufacturer in question, and the stability issues were overly exaggerated, the truth of the matter was that the motherboard manufacturer produced well made boards, and that was that. 

What is this brief story getting at?  The key to the effective use of capacitors on a motherboard isn't the size nor the population, rather the location of the capacitors.  The general rule of thumb is that so long as the signal present between any frequently "trafficked" components on a motherboard (those that are sensitive to fluctuations in voltage, etc...) retains its original strength, the operation of the board has a greater chance of being stable.   In order to ensure this, motherboard manufacturers place capacitors to keep the signal between two points on a motherboard both clean and strong, improving the stability and reliability of the motherboard, and thus explaining any issues that come up during the tests that could possibly be capacitance related.  ABIT's effective use of capacitors around the ATX power supply connector, Socket-370 interface, 443ZX controller chip, memory banks and AGP slot explain the results AnandTech's ZM6 sample exhibited during the stability tests.  Comparatively speaking, when pitted against the other Socket-370 based motherboards AnandTech has reviewed thus far, the ABIT ZM6 is on par with Microstar's MS-6153, as it crashed but once during the stability tests.

The rest of the motherboard's features are fairly standard to ABIT motherboards, for those of you that aren't familiar, the description of the board's SoftMenu II Jumperless CPU Setup and it's other features have been taken from the AnandTech BX6 Revision 2 Review:

As we have all come to expect from ABIT, the ZM6 features the latest and greatest version of their SoftMenu II Jumperless CPU setup.  With the BH6, ABIT introduced the ability to modify the SEL66/100# setting, enabling the user to effectively unlock the clock lock on 100MHz FSB processors running at the 100MHz FSB.  For example, the original Pentium II 350 only allowed a 3.5x clock multiplier when using the 100MHz FSB, making 400MHz impossible, and anything greater than 350MHz impossible without the use of a higher FSB setting (i.e. 112MHz).   Setting the SEL66/100# setting to "Low" allowed for the removal of this lock, giving many users the ability to run their 350MHz Pentium II processors at 100MHz x 4.0 or 100MHz x 4.5, and their 400MHz Pentium II's at 100 x 4.5.  The SEL66/100# feature has made its way into the SoftMenu II setup of the ZM6, however with a Celeron CPU, the usefulness is absolutely nothing as there won't be a 100MHz FSB Celeron processor for quite some time.

The ZM6 would have little to offer over the competition if it weren't for a few more modifications to SoftMenu II, ABIT's sole reason for existence right now in the overclocking market.  The ZM6's SoftMenu II brings a few new settings, such as the inclusion of the new higher frequency FSB settings (138MHz, 143MHz, 148MHz, 153MHz) as well as "in-between" settings such as the 110MHz and 120MHz options for those users that just can't seem to hit 112MHz or 124MHz with their systems.  The board also supports the 1/4 PCI clock divider with all > 100MHz FSB settings to keep the PCI frequency as close to the specified 33MHz setting as possible, for those with extremely tolerant PCI peripherals.

The AGP clock is also derived from the FSB frequency, and the ZM6's SoftMenu II does offer the ability to select from a 1:1 or a 2:3 FSB ratio for the derivation of the AGP frequency, keeping the clock as close to the rated 66MHz frequency as possible.  Complaining about ABIT not including any other AGP ratios is quite futile as the motherboard has nothing to do with the AGP frequency, which is actually stored in the chipset itself and only selected through the motherboard, leaving the 1:1 and 2:3 ratios as the only two options with the BX chipset.   It looks like we'll have to wait for Intel's 440JX (Camino) chipset before we can see any other AGP clock ratios. 

ABIT's highly regarded User's Manual makes its presence felt in the box of the ZM6 giving users a step-by-step installation and a configuration guide for their system.  The ABIT manual includes a fairly easy to read and useful explanation of the BIOS and CPU setup, and makes the overall experience with the new ZM6 (especially for first time system builders) a pleasant one.

The ZM6, as expected, also features ABIT's core voltage manipulation option which allows the user to select core voltage settings ranging from 1.30v to 2.30v in 0.5v increments, meaning the board will also support any upcoming Celeron processors based on the Katmai (Pentium III) core.  Don't worry, those won't be around for quite some time however.  Unfortunately, the overclockability of Celeron processors makes the usefulness of the 100MHz+ FSB settings on the ZM6 pretty useless, as there isn't a single Socket-370 Celeron processor (with the exception of the 300A) that even remotely has a chance of using the 100MHz FSB due to its locked clock multiplier, much less anything faster than 100MHz.

If it weren't for the fact that the ZM6 exhibited top notch stability (in comparison to other Socket-370 boards), ABIT would have been in a very bad position, with an overclocker's board, yet with nothing to overclock.   Luckily, the ZM6 is quite stable, and it's easy to setup nature makes it the ideal Socket-370 board provided that you are in the market for one.

The Bad

As a reader of AnandTech pointed out (thanks Andrew), the ZM6, in spite of the specifications listed on ABIT's website and in ABIT's manual, is missing a second surface mounted thermistor for measuring ambient case temperature.  Depending on the type of user you are, its absence may or may not be of any value to you, but do note that it was absent from the sample AnandTech tested.

Finally, as mentioned in virtually all Socket-370 motherboard reviews on AnandTech, the Socket-370 platform is not the most ideal platform to pursue at this time.  With no future plans for Socket-370, your best bet would be to stick to Slot-1, and if you happen to be falling for the "Socket-370 is cheaper" hype this next fact may be a bit of an eye opener.  At the time of publication of the ABIT ZM6 review, the price difference between a Socket-370 Celeron and a Slot-1 Celeron was, on average, $1.  Is that enough to justify going with a Socket-370 system over a Slot-1 system? 

USB Compatibility

• Number of Front Universal Serial Bus Root Ports: 0

• Number of Rear Universal Serial Bus Root Ports: 2

• USB IRQ Enable/Disable in BIOS: Yes

• USB Keyboard Support in BIOS: Yes

Recommended SDRAM

SDRAM Tested: 1 x 64MB Mushkin PC100 SDRAM; 1 x 64MB Memory-Man PC100 SDRAM

Manufacturer: The Memory Man
Purchase Web-Site: http://www.memory-man.com

Manufacturer: Mushkin
Purchase Web-Site: http://www.mushkin.com

The Test

In recent times, choosing a motherboard cannot be completely determined by a Winstone score. Now, many boards come within one Winstone point of each other and therefore the need to benchmark boards against each other falls. Therefore you shouldn't base your decision entirely on the benchmarks you see here, but also on the technical features and advantages of this particular board, seeing as that will probably make the greatest difference in your overall experience.

How I Tested

• Each benchmark was run a minimum of 2 times and a maximum of 5 times, if the motherboard failed to complete a single test within the 5 allocated test runs the OS/Software was re-installed on a freshly formatted Hard Drive and the BIOS settings were adjusted to prevent the test from failing again.  All such encounters were noted at the exact time of their occurrence.

• Business Winstone 98 & 3D Winbench 98 was run at each individually tested clock speed, if reliable scores were achieved with the first two test runs of the suite an average of the two was taken and recorded as the final score at that clock speed.  If the test system displayed erratic behavior while the tests were running or the results were incredibly low/high the tests were re-run up to 5 times and an average of all the test runs was taken and recorded at the final score at that clock speed

• All video tests were conducted using an AGP video accelerator

• No foreign drivers were present in the test system other than those required for the system to function to the best of its ability

• All foreign installation files were moved to a separate partition during the test as to prevent them from effecting the test results

• All tests were conducted at 1024 x 768 x 16-bit color

• Quake 2 tests were conducted at 800 x 600 x 16-bit color in Software Rendering Mode

The Final Decision

At a price lower than that of the BM6, the ZM6 can be considered the best overall Socket-370 motherboard thus far.  Although Microstar came quite close with their competitive entry into the market, the general feel of ABIT's SoftMenu II Jumperless CPU Setup still dominates the hearts of most that are interested in jumperless motherboards and the overall design and stability of the ZM6 coupled with the decreased cost make ABIT's latest entry into the Socket-370 market a promising one. 

How it Rates

Click Here to Learn about AnandTech's Motherboard Testing Methodology