Original Link: https://www.anandtech.com/show/82

ABIT has come a long way since the early days of their attempts at competing with some of the big names in the industry such as ASUS and AOpen, however they are at a point right now where they pose a threat to those who at one time or another ruled the market completely.  ABIT's first real success was the IT5H, and after the amazing release of such an excellent motherboard by a virtually unknown company at the time ABIT was pressed to shift into high gear, in order to play with the big boys.  Hitting the market with immensely successful motherboards ranging from the blazing fast AX5 to the rock solid TX5N and the affordable PD5N, ABIT is fighting for the throne of best motherboard manufacturer in the industry.  In order to achieve that position ABIT knows that they must do much more than stick to the Socket-7, so what better way to prove themselves than releasing a knockout Pentium II LX motherboard.

Look for this sticker on the last ISA slot of the ABIT LX6, if the last numbers on the first line don't read 1.0 or above return the board

Since the LX6 was first announced quite a few pre-release versions emerged, although they were mostly confined to hardware testers and magazine editors they did find their way into the mainstream market.  What to look out for when shopping for a LX6?  The motherboard revision number should be NO LESS THAN 1.0, and the BIOS should be dated around 11/03/97 and it shouldn't be an "Evaluation ROM".   As long as your LX6 meets those preceding requirements we'll be looking at the same motherboard, however if your LX6 doesn't meet any one of the above stipulations don't expect it to be anything like the final revision LX6 reviewed here.  If your vendor happened to ship you a pre-release LX6 demand a RMA, do not settle with the motherboard you have since it most likely has quite a few problems that a simple exchange could fix.

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Motherboard Specifications

Socket Style:	Slot-1
Chipset:	i82440LX
Cache:	N/A (On Chip)
Form Factor:	ATX
BUS Speeds:	60 / 66 / 68 / 75 / 83 / 100 MHz
Clock Multipliers:	2.0x / 2.5x / 3.5x / 4.0x / 4.5x / 5.0x
Voltages Supported:	1.5v - 3.5v (Auto Detect)
RAM Slots:	4 168pin DIMM Slots (EDO/SDRAM)
AGP/PCI/ISA Slots:	1 AGP Slot 4 PCI Slots 3 ISA Slots (1 Shared / 3 Full Length)
BIOS:	AWARD PnP BIOS w/ SoftMenuTM Jumperless CPU Configuration
PCI EIDE Controller:	Super I/O 2 EIDE Channels 1 FDD Channel 2 Serial /1 EPP

 

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The Good

Start from the bottom and build up.  That was ABIT's philosophy when they designed the IT5H and it is evident that it was the same philosophy used when the LX6 was designed.  One of the most important things to realize as an engineer is that you cannot slack off in one area of your design in order to compensate for excelling in another area.  Most LX boards that have been released feature a ridiculous 3 SDRAM DIMM slots instead of a full set of 4 DIMM slots to make expansion a bit easier.  ABIT on the other hand, started with the basic requirements for an excellent motherboard, 4 DIMM slots, 3 ISA slots, 4 PCI, 1 AGP, and moved on from there.

Due to the inclusion of an AGP slot in all LX motherboard designs we must realistically limit ourselves to 3 ISA & 4 PCI slots or vise versa (2 ISA slots is simply out of the question at this point in time).  Since most newer peripherals are PCI based, it would make sense to include more PCI than ISA slots while remembering not to sacrifice expandability to compensate for any other aspect of the motherboard itself.   The LX6 also features a total of 5 external fan connectors for added cooling...wonder why ABIT decided to include so very many connectors?  Keep on reading to find out what the LX6 offers that has the critics, including myself, begging for more cooling...

Like all newer ABIT motherboards, the LX6's user manual can sometimes referred to as a crash course in engineering due to its incredible attention to detail.  This has come to be expected from ABIT in all of their motherboards and their excellent writing style used in the included written documentation of the LX6 (as well as other ABIT motherboards) makes the initial setup and configuration your new purchase a pleasing one.  The only part of the ABIT manual which is lacking detail, as is nearly every other motherboard manual in the world, is a description of the Chipset Features of the BIOS Setup Utility, information that is critical to getting the most performance out of your system.     

The LX6's layout conforms fully to the ATX specification, which makes installing the LX6 in your ATX case a breeze.  Like most newer ABIT motherboards, the LX6 features the popular SoftMenuTM Jumperless CPU Setup utility which integrates nicely into the commonly known AWARD BIOS Configuration package.   The SoftMenuTM Utility allows the user to select the CPU clock speed from a number of internally preset options, or the user can simply specify the bus speed/clock multiplier manually, this feature found in most newer LX motherboards under different names of course makes overclocking the LX6 almost second nature.

The LX6 features a fully operational menu containing the selectable 60, 66, 68, 75, 83, and 100MHz bus speeds in the SoftMenuTM Setup utility.  The most highly anticipated feature of any motherboard to date has been the inclusion of a 100MHz bus speed setting, and unexpectedly ABIT has provided us with this setting that has been passed around as a mere rumor for quite some time.  Originally designed for Internal Testing *ONLY* the ABIT LX6's 100MHz bus speed setting was never intended to make it to the mainstream market as a functional option, however when the pre-release boards made it into the hands of testers we began to speculate as to why the setting was even included in the SoftMenuTM setup if it wasn't going to be used for any purpose.  The internal testing of the LX6 at the 100MHz bus speed was supposed to be conducted on a special version of the Pentium II and left alone never to be used again.  However when the thought of running current Pentium II processors at the 100MHz bus speed ABIT's eyes lit up...as did the eyes of thousands of overclockers all around the world.  Could ABIT redeem themselves after the horror stories of the pre-release LX6 made their way into the public's ears by simply enabling this 100MHz bus speed?

uction revision to increase both performance and stability made the final revision of the LX6 a killer motherboard as well as a successful chance of redemption on ABIT's part.

After enabling the 100MHz bus speed setting the now functional SoftMenuTM utility one thing quickly comes to notice, the BIOS cannot recognize the newly implemented bus speed since it reports the CPU speed as if the bus speed was set to a lower 83.3MHz setting.  Does this mean that the 100MHz bus speed doesn't work?   Most definitely not!  Further tests and benchmarks show that the actual clock speed of the CPU, when using the 100MHz bus speed, does not reflect an 83.3MHz setting...however it also doesn't reflect a 100MHz setting either!  What's up with the LX6's clock crystal?  Figure 3. (Left) Those chips you see there are what make the 100MHz bus speed setting on the LX6 possible, you can thank them for the performance you receive from the LX6 at the 100MHz setting.

When the motherboard interprets the signal it receives from the user to enable the 100MHz setting internally the clock oscillator, not designed for operation within that specification, does the best job it possibly can to reach that 100MHz setting.  However, the actual bus speed used when the 100MHz setting is activated fluctuates in a direct variation to the processor clock multiplier, for the most part.  When the clock multiplier of the CPU was lowered from 4.0x to 3.0x the approximate memory bus speed of the LX6 jumped up from 91.5MHz to a whopping 106.6MHz!!!  However when the clock multiplier was raised to 3.5x the bus speed dropped to a incredibly low (low when compared to the previous 106.6MHz mark) 90.57MHz.   For the most part the higher bus speeds were achieved with lower clock multipliers, however that doesn't ALWAYS hold true.  The LX6 will randomly boot at the lowest possible CPU bus speed of 89.0MHz when set to the 100MHz setting in SoftMenu^TM regardless of the clock multiplier in which case you receive a performance boost nearly equivalent to that which you would receive if you had enabled the 83.3MHz frequency in the BIOS.  The 100MHz setting results in a bus clock frequency ranging from the lowest setting of approximately 89.01MHz to the peak at about 106.67MHz with the most commonly achieved speeds lying in the 91.115MHz to 94.5MHz region.   What good is a 100MHz bus speed setting if nothing will operate when using it?   No good at all...HOWEVER the LX6, when used with the proper peripherals, displays its excellent stability even at the 100MHz bus speed.  With 2 x 32MB of Advanced Megatrends SDRAM the LX6 could be set to the absolute fastest BIOS timings and it would complete all tests at the 100MHz bus speed setting.  It should be mentioned now that even with a genuine Pentium II - 300 the highest the LX6 would boot at was 377MHz (~94.3MHz x 4.0) and the 100MHz x 4.5 setting wouldn't work at all (oh darn...looks like we'll have to wait for the 333MHz Pentium II to clock it at > 400MHz =)...)  For your convenience, here is a list of peripherals that have passed the test at the 100MHz bus speed with the LX6:

Now I realize that the above list is not a very comprehensive one, however the main hot-spots to look for when diagnosing a system that won't boot at the 100MHz setting are your Video Card, and Memory.  There are reports of the STB Velocity 128 not working at the 100MHz setting, I cannot personally confirm nor deny those claims until I receive my STB cards for testing.

As mentioned earlier, the stability of the LX6 is truly first class...however the LX6 isn't populated with ANY oversized tantalum capacitors...so how could it possibly be a stable motherboard?  History has shown us time and time again that size isn't all that matters, just take a look at our computers today and compare them to the good old Eniac which was about as powerful as a hand held calculator yet completely filled up a few rooms in sheer size.  The LX6's 15 mid-sized capacitors are carefully positioned around the motherboard with high concentrations around the Slot-1 IC, and the 7 onboard switching voltage regulators which also add to the LX6's incredible stability.  In all of the tests that were run on the LX6, the test system only crashed once when using 2 x 32MB sticks of Corsair SDRAM with the absolute fastest timings in the BIOS Chipset Features Setup. 

ABIT seems to have fixed every single problem that plagued the pre-release LX6 including its incompatibility with the Enlight 72xx series 250W power supply.  The final revision LX6 now works perfectly with the Enlight power supplies and doesn't seem to have any other noticeable problems, just to safely test the 100MHz setting the test system was left running quite a few memory/CPU intensive tasks overnight.  The result?  The LX6 is one of the fastest and most stable Pentium II motherboards in the world today!  ABIT took the world by surprise when they released their IT5H over a year ago and they have done it again with the LX6.  

The Bad

The only real problem with the LX6?  A lack of high quality tantalum capacitors on the LX6 makes its future reliability unpredictable...running your system for months at the 100MHz bus speed setting could prove to be very hazardous...but then again it might not =)

IRQ Usage

• Allows user to release PCI VGA IRQ

• Allows user to individually assign IRQs to PCI/Legacy ISA devices

• Autodetects PnP Peripherals after POST

Recommended BIOS Settings

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.

Test Configuration

In spite of the 100MHz bus speed setting the LX6 can still be beat by the AOpen AX6L, its biggest competitor. However, do not take the Winstone scores into consideration exclusively. Have a look at the LX6's performance in the individual categories of memory, disk, and video performance.

Here the performance of the LX6 is beginning to seem more and more worthwhile. The Uncached Performance of the test drive under Wintune 97 was an incredible score as well as the RAM benchmarks. How much of an increase in performance does the 100MHz bus speed give you over the 66MHz bus speed in a real world test? To find out let's fire up Quake =)

Using the fluctuation in the actual bus speed put into operation when the 100MHz setting is activated on the LX6 to my advantage I managed to get the Pentium II as close to a real 300MHz as possible with the 100MHz setting. However since the 83.3MHz x 3.5 setting results in a clock speed of about 291MHz and to illustrate the raw performance increase of the 100MHz bus over the 66MHz standard the Pentium II, when using the 100MHz setting, was clocked at approximately 275MHz which is as close as I could get it to the 291MHz of the 83.3 x 3.5 test run without going over by too much. The Quake tests prove that the 100MHz bus speed, when applied to the Pentium II processor, provides a maximum of a 16% increase in video performance with a realistic increase around 5 - 11%. One must realize that the reason for such a low increase in performance is because the L2 cache of the Pentium II runs at 1/2 the processor's clock speed and therefore has nothing to do with the actual bus speed of the CPU if the resulting clock speed is still the same. For example, the 66.6MHz x 4.5 setting results in a clock speed of about 300MHz, as does the 75MHz x 4.0 setting. The L2 cache in both situations operates at 1/2 clock speed, with 1/2 * 300MHz being 150MHz. Therefore by increasing the bus speed from 66MHz to 75MHz you see very little improvement in speed. The distance between the 83.3MHz setting and the 91.6MHz bus frequency achieved with the LX6 is almost non-existent as shown by the Quake and S/VGA Bench tests. The most dramatic performance increase when using the 100MHz setting over the 83.3MHz setting is the 4% increase in your Quake frame rate at 640 x 480. Is the 100MHz bus speed setting worth it? Yes, however don't expect it to absolutely knock your socks off...we've waited so long for it to appear, and now that we have it we're beginning to realize that it isn't all that it was cracked up to be. It seems like we'll have to do a little more waiting before we can truly see the positive effects of the 100MHz bus speed.

The Final Decision

The LX6 right now is probably your best bet for a fast, stable, and reliable LX based Pentium II board. Its combination of expandability features, performance, and overall quality including its unique support for the 100MHz bus speed make the LX6 is sure fire winner. Who will dethrone ABIT? We can't say for sure now, however whoever it is will have to have one he!! of a motherboard to beat this. Especially considering the fact that the LX6 can be picked up for under $200! ABIT's challenge to the motherboard world? Name a motherboard that is fast, stable, and affordable. I like to call it an ABIT.