Gigabyte GA-X38-DQ6 Mainboard Review

The Intel X38 based mainboard with DDR2 SDRAM support from Gigabyte pleased us with the absence of some frustrating drawbacks we have seen before. Let’s find out if the improvements made to this board make it worth our recommendation to computer enthusiasts.

by Ilya Gavrichenkov
11/29/2007 | 03:26 PM

I believe last week was the most remarkable period of time for computer fans in the entire 2007. It is when AMD finally launched their so long awaited Phenom processors. Although they couldn’t really please their fans with this launch. What we have been seeing so far is that the CPUs didn’t make the best impression: working at the same frequency they lose to the competing Core 2 Quad solutions. Besides, their working frequencies are overall pretty low. Most of the previews available online these days showed that AMD engineers didn’t manage to push the micro-architecture to the desired level as well as failed to ensure acceptable yields for chips running at satisfactory frequencies.


All this means that computer enthusiasts will hardly have any questions about what a featured platforms should be these days. Intel processors will stay the fastest solutions in the first half of next year. Especially since we can expect a new promising Penryn processor family from Intel to launch in January and our tests have already shown that they will deliver even higher performance (for details see our article called Second Iteration of Core Micro-Architecture: Intel Core 2 Extreme QX9650 CPU Review).

As for the best contemporary LGA775 platform compatible with the today’s as well as upcoming processors, luckily there are quite a few alternatives available to computer users at this time. Numerous mainboards on Intel P35 and Intel X38 officially support Penryn processors. The first group of products on P35 has already been studied very carefully on our site and will hardly pose any questions. As for X38 based mainboards, they just start appearing in stores that is why they become extremely interesting. They cost more, but only mainboards like that can support faster PCI Express 2.0 x16 graphics card bus, which will be a very demanded features taking into account the upcoming arrival of the new graphics accelerator generation.

Therefore we decided to take a real close look at the mainboards based on this new chipset. Moreover, we decided to focus first on those solutions that work with DDR2 SDRAM, which is more promising these days not only in terms of broader availability but also from the performance prospective. We have already reviewed one mainboard like that from Asus (see our Asus P5E Mainboard Review), and today we would like to discuss a solution from another first-tier manufacturer – Gigabyte.

I have to point out right away that like many overclocking fans out there we have very mixed feelings about Gigabyte mainboards. Trying to catch up with the market leader, this manufacturer has been adding a lot of marketing “technologies” to its products, although some of them didn’t always make sense. Therefore, top Gigabyte mainboards based on P35 chipset have been criticized a lot for the excessive enhancements that made these solutions really difficult to work with (see our Gigabyte GA-965P-DQ6 (rev.2.0) Mainboard Review). Luckily, the company engineers took all the criticism into consideration and did a good job on the new X38 based series: almost all existing issues have been eliminated and new Gigabyte boards look more than worthy at first glance. In fact, our today’s review will try to answer the following question: have Gigabyte new mainboards acquired the same chance to become a good basis for an overclocked gaming platform as competing Asus solutions? So, we are going to discuss this matter in great detail today with the help of our main hero – Gigabyte GA-X38-DQ6 mainboard – the top mainboard on X38 from this vendor supporting DDR2 SDRAM.

Package, Accessories and Technical Specification

All in all, Gigabyte GA-X38-DQ6 is designed like Intel P35 mainboards: in addition to standard chipset controllers the features of the end product are expanded by a pair of Gigabit network controllers, IEEE1394 controller and an additional IDE RAID controller. As a result, the mainboard and its formal specifications look as follows:

Gigabyte GA-X38-DQ6


LGA775 processors: Celeron, Pentium 4, Pentium D, 
Pentium 4 XE, Pentium XE, Core 2 Duo, 
Core 2 Quad and Core 2 Extreme


Intel X38 (X38 MCH + ICH9R)

FSB frequency

100-700MHz (with 1MHz increment)

Overclocking friendly 

Adjustable voltages: processor Vcore, Vmem, FSB, 
PCI-E, North and South Bridge.
Independently adjustable PCI Express bus frequency.


4 DDR2 DIMM slots 
for dual-channel DDR2-1067/800/667/533 SDRAM

PCI Express x16 slots

2 PCI Express 2.0 x16 slots

PCI Express x1 slots


PCI expansion slots


USB 2.0 ports

12 (8 – on the rear panel)

IEEE1394 ports

3 (2 – on the rear panel)


1 ATA-133 channel 
(by Gigabyte SATA2 controller, with RAID support)

Serial ATA

6 Serial ATA-300 channels 
(in the chipset, with RAID support)
2 Serial ATA-300 channels 
(by Gigabyte SATA2 controller, with RAID support)

ATA RAID support

RAID 0, 1, 0+1, 5 in the chipset

RAID 0, 1 by Gigabyte SATA2 controller

Integrated sound

8-channel HD codec: Realtek ALC889A

Integrated network

2 x Gigabit Ethernet 
(two Realtek RTL8111B controllers)

Additional features



Award Modular BIOS v6.00PG


ATX, 305mm x 244mm

Despite almost the same features with the Intel P35 based solutions, Gigabyte GA-X38-DQ6 is more expensive: it sells for $260. The reason for that is the Intel X38 chipset positioning. It is targeted for high-performance systems and the chipset itself is $20 more expensive than the predecessor.

The mainboard comes in a pretty large colorful box that can be unfolded open to reveal the detailed description of the product advantages.


The package designers did a really good job on making sure that the mainboard will become an eye-stopper: there is also a transparent plastic window that shows a part of the cooling system and an embossed plastic DQ6 logo on the front side of the box.

Inside the external box there is the mainboard itself packed into a transparent plastic casing and a separate smaller box with accessories bundle. Gigabyte GA-X38-DQ6 is not a cheap product that is why it comes with the whole bunch of different things. The standard set includes a traditional user’s manual, additional paper materials, a CD disk with drivers, I/O Shield for the case rear panel, four SATA cables, PATA and FDD cables. Besides, Gigabyte also offers two brackets for the case rear panel that carry the total of four SATA ports and two standard Molex connectors for the power supply. There is also a pair of cables that allows connecting regular SATA hard drives to these ports. In addition to that and as a free bonus there is a Gigabyte logo sticker that goes onto the front of your system case and two small but extremely important screws, which we are going to talk about later in our review.

Closer Look

At first glance Gigabyte GA-X38-DQ6 looks like a pretty common contemporary LGA775 mainboard. Like many other similar products it is equipped with four DIMM slots for DDR2 SDRAM and two PCI Express x16 slots for s single or dual graphics card configuration. The mainboard currently supports Crossfire technology that allows using a dual-graphics card configuration built with ATI based cards. The alternative SLI technology is not yet supported: this technology is not supported for Intel chipsets in Nvidia drivers. However, the PCI Express x16 bus supports 2.0 specification, which provides twice the bandwidth with new graphics cards (so far only Radeon HD 3800 and GeForce 8800 GT support PCI Express 2.0 x16).

I would like to remind you that another peculiarity of the PCI Express 2.0 x16 slots is the higher capacity of the power lines that can ensure proper operation of 150W graphics cards without any additional cabling necessary. That is why Gigabyte GA-X38-DQ6 features the third standard MOLEX power connector located right next to the 24-pin ATI connector. You should use this connector if the system is equipped with powerful graphics accelerators (especially two of them) that can overload the standard power lines of the old power supply units.

There is one thing that stands out among all other features of the Gigabyte GA-X38-DQ6 mainboard. This feature is specifically high-lighted on Gigabyte’s web-site as well as on the mainboard package. It is support of 1600MHz system bus. Intel is going to release a different core logic set aka X48 specifically for work with processors supporting 1600MHz FSB. However, Gigabyte GA-X38-DQ6 already offers this feature today, especially since all other differences between X38 and X48 will be minimal.

And the manufacturer’s promises are not just words. During our test session Gigabyte GA-X38-DQ6 worked absolutely stably with a Core 2 Extreme QX9770 processor on Penryn core that uses 1600MHz bus.

No wonder that Gigabyte engineers paid special attention to implementing a high-quality 6-phase processor voltage regulator circuitry. We were a little puzzled by the manufacturer’s intention to present it as a 12-phase voltage regulator, but this is not true, because there is a regular ISL6327 chip used in it. The voltage regulator is built with high-frequency power MOSFET that guarantees its longer life cycle as well as higher efficiency at lower operational temperature. At the same time the voltage regulator as well as the rest of the mainboard features solid-state capacitors with organic polymer electrolyte that are also extremely reliable.

Although the CPU voltage regulator circuitry is designed in such a way that no cooling is necessary, it still features a heatsink that is connected to the chipset North and South Bridge heatsinks with the heatpipes. Of course, the main intention of the Gigabyte engineers was to ensure better heat dissipation from the core logic components rather than the CPU voltage regulator.

The developers’ efforts were not vain. This passive cooling system with a unique marketing name “Silent Pipe” is pretty efficient. Despite high heat dissipation of the Intel X38 chipset, the cooling system works well even without additional fans. The system owes its success to solid copper heatsinks with thin rib arrays and three heatpipes: one connecting the heatsinks on top of the chipset North and South Bridges, and the other two – leading to the additional heatsink fastened on top of the processor voltage regulator.

Silent Pipe cooling system doesn’t strike you as massive. For example, Asus mainboards come equipped with much bulkier heatsinks. However, you may still encounter some problems with installation of large processor coolers on Gigabyte GA-X38-DQ6 mainboard. However, you shouldn’t really blame the heatsinks, but the DIMM slots placed too close to the processor socket. For example, during our test session we managed to install Scythe Infinity processor cooler only in one position: with the fan turned towards the rear end of the board.

And now I would like to say a few words about the most troubling part of the Gigabyte mainboards design. Most overclockers are very concerned about another part of the cooling system known as Crazy Cool. It is an aluminum plate with shallow ribbing fastened at the bottom of the board right beneath the processor socket and chipset North Bridge. Unfortunately, this plate does more harm than good. Firstly, it doesn’t allow you to install any processor coolers that require a backplate and these models are pretty numerous currently. Secondly, it hinders natural bending of the mainboard PCB thus making it harder to fasten those cooler that use plastic clips as retention.

Unfortunately, the previously tested Gigabyte mainboard didn’t allow us to easily remove the Crazy Cool system, because it served as a bottom part of the chipset Silent Pipe cooling system retention at the same time. This was one of the primary reasons why we couldn’t recommend top mainboards from Gigabyte to computer enthusiasts. Luckily, Gigabyte GA-X38-DQ6 has been significantly improved from this standpoint. Now they include two additional screws that can be used instead of the Crazy Cool system to hold the chipset cooling solution. The use of these screws allows removing the harmful plate and makes the board compatible with almost any processor cooler.

It is very nice that Gigabyte developers have listened to overclockers’ requests and made the right conclusions. Now we should simply wait for Crazy Cool to be completely removed from the boards: it will definitely be a victory of common sense.

As for the overall PCB layout, it is free from significant drawbacks, although it is still not absolutely ideal. In most cases you should have no problems assembling and working with a Gigabyte GA-X38-DQ6 based system.

I would like to draw special attention to the mainboard rear panel that is stuffed with all sorts of connectors. There are a lot of ports there. As a result, Gigabyte GA-X38-DQ6 hardly needs any additional rear panel brackets. The mainboard rear panel carries 8 USB 2.0 ports, two different IEEE1394 ports, two Gigabit network controllers, PS/2 connectors for keyboard and mouse, an optical and coaxial SPDIF output port and six analogue audio-jacks.

Another indisputable advantage of Gigabyte GA-X38-DQ6 is the eight SATA2 channels, six connected via the chipset South Bridge and two more are implemented via the brand name RAID controller together with the PATA interface.


The Gigabyte GA-X38-DQ6 mainboard was tested with the BIOS version F6b dating back to October 30, 2007.

The interface of our mainboard’s BIOS Setup is quite traditional. The BIOS is based on Award 6.00PG microcode used in most contemporary mainboards. However, we should give due credit to Gigabyte engineers who managed not only to structure all settings in a very smart manner, but also introduced a few very useful utilities into the BIOS itself. Moreover, Gigabyte GA-X38-DQ6 mainboard supports Dual BIOS technology that implies the existence of a spare Flash memory chip with a BIOS copy onboard, which saves the day if the main BIOS dies.

Almost all the options dealing with the main system parameters configuration are gathered together in a separate BIOS section called MB Intelligent Tweaker (M.I.T.). This particular section will be especially interesting to overclocking fans.

Here you can set the processor clock multiplier and FSB frequency that can vary between 100 and 700MHz with 1MHz increment. Also, you can configure the dynamic CPU overclocking tools that adjust the processor frequency depending on its current workload – C.I.A.2.

BIOS Setup of our mainboard also offers automatic graphics card overclocking technology called Robust Graphics Booster.

The memory subsystem frequency on our board can be set with dividers – juts like on solutions based on previous generation Intel chipsets. Gigabyte GA-X38-DQ6 offers a full range of FSB:Mem coefficients supported by Intel X38 chipset. Note that FSB Strap frequency is set together with the divider, it is present as a remark to each divider in the corresponding menu section. It is very nice to see the current and new memory frequency right next to FSB:Mem setting spot, as it makes memory configuring much easier.

Note that the new Intel X38 chipset unlike Intel 975X doesn’t have any reducing memory frequency dividers. That is why the memory frequency in Gigabyte GA-X38-DQ6 based systems cannot be lower than FSB frequency. You should keep it in mind when assembling a platform for overclocking needs.

Next to the DDR2 SDRAM frequency settings there is a menu item called Performance Enhance. It allows you to choose from three available options: Standard, Turbo and Extreme. This setting used to affect the memory subsystem performance significantly on Gigabyte mainboards based on Intel P35 chipset: it adjusted the Performance Level. However, things are different on Gigabyte GA-X38-DQ6: it looks like this setting has no effect at all here. At least, not in the currently available BIOS versions.

The fact that Gigabyte changed its attitude to computer users can be seen not only from the changes in the chipset cooling system design. It also found its way into the mainboard BIOS that has no hidden areas on GA-X38-DQ6. All configuration options are available immediately including memory timings that used to be hidden in the previous mainboard models.

The list of adjustable parameters with their supported ranges is given in the table below:

When being configured, the mainboard displays the current parameter values and allows setting the above listed parameters as Auto, which makes the configuration process easier for inexperienced users.

However, if the mainboard wouldn’t boot after you adjusted its settings, it will automatically reset all BIOS settings to defaults. Unfortunately, though, you will get no warning about this measure, the mainboard would just continue booting with non-optimized settings.

As for the voltage adjustment, our mainboard offers the following options:

All voltages except processor Vcore are adjusted as relative values. The actual numbers can only be set for the processor core voltage. There is a very convenient information string showing the actual default voltage for your system CPU right next to the Vcore adjustment field.

BIOS allows increasing the chipset North Bridge and memory voltages by additional 10% for extreme overclocking needs. There you will also find CPU GTL Reference Voltage adjustment options that are very useful during quad-core processor overclocking.

Lowering of actual processor Vcore is a pretty widespread problem that didn’t miss Gigabyte GA-X38-DQ6 mainboard, too. This unpleasant effect becomes especially visible in case of overclocked quad-core processors. Our measurements performed for Core 2 Quad Q6600 processor working at 3.6GHz showed that in idle mode the processor Vcore turns out about 0.04V lower than the BIOS setting. And in case of full CPU utilization is simply starts varying back and forth. Moreover, the maximum Vdroop may sometimes hit 0.074V. The voltage drop is not as dramatic with dual-core CPUs, however, you shouldn’t disregard this effect during overclocking.

Besides the most important overclocking section called MB Intelligent Tweaker (M.I.T.) you should also pay attention to some other BIOS Setup options.

For example, the PC Health Status page with all hardware monitoring functions:

Note that the mainboard allows controlling the processor cooler fan rotation speed depending on the CPU temperature readings.

Processor technologies can be configured in the Advanced BIOS Features section.

Gigabyte engineers also made sure that the settings profiles can be saved for future use. The mainboard allows saving up to 8 settings profiles. Note that the good settings profiles, i.e. when the board booted safely, will be saved automatically.

Also Gigabyte GA-X38-DQ6 BIOS boasts built-in Q-Flash utility that allows updating the BIOS without loading the OS.


Compared with the previous Gigabyte solutions from DQ6 series, GA-X38-DQ6 has quite a few changes that should make it more overclocking friendly. The mainboard cooling system is compatible with most processor coolers, the BIOS Setup has no hidden sections, and system monitoring displays the numeric voltage values. All this is clear indication that Gigabyte developers started taking overclocking fans much more seriously.

To check out the overclocking potential of the Gigabyte GA-X38-DQ6 mainboard, we assembled a special testbed including the following equipment besides the board itself: 2GB DDR2 from Corsair (Dominator TWIN2X2048-10000C5D), OCZ GeForce 8800GTX graphics card, Western Digital Raptor WD1500AHFD HDD and SilverStone SST-ST85ZF power supply unit. We used a Scythe Infinity processor cooler, too.

First of all we decided to determine the maximum FSB frequency when the board would remain stable and reliable with a dual-core processor. We used a Core 2 Duo E6750 processor. For stability check we ran Prime95 25.3 program for 30 minutes in Large FFT and Blend modes.

We encountered no problems here: the mainboard worked fine at FSB speeds beyond 500MHz. By raising the North Bridge voltage 0.15V above the nominal we got the system to run stably at 520MHz FSB. And the increase in the North Bridge voltage by 0.175V pushed our test processor to 525MHz FSB that is its FSB Wall.

The memory was clocked synchronously with FSB in this case and functioned at 1050MHz with 4-4-4-12 timings.

Note that it was very simple to overclock our CPU in this case. To obtain the above mentioned result we didn’t have to try all sorts of settings. All voltages except processor Vcore, Vmem and North Bridge voltage were set to Auto.

The second overclocking experiment was performed on a quad-core Core 2 Extreme QX6850 processor. These CPUs are known to overclock a little worse on the FSB side than their dual-core counterparts.

As soon as the FSB frequency reached 450MHz, we had to increase the chipset North Bridge voltage by 0.1 to ensure system stability. Further FSB frequency increase was only possible with dramatic growth of this voltage. For example, at 465MHz FSB the chipset North Bridge voltage had to be raised by 0.3V, otherwise the system stability was questionable. By the way, at the same time we had to increase the FSB voltage by 0.1V, too.

The maximum FSB frequency when our mainboard remained stable with a quad-core processor equaled 475MHz.


We managed to exceed this number by raising the North Bridge voltage by 0.4V and setting the FSB OverVoltage Control at +0.2V.

Together with the FSB overclocking of a quad-core processor, we confirmed that Gigabyte GA-X38-DQ6 can work with the memory clocked at very high speeds. With the FSB:Mem divider set at 3:4 we managed to speed up DDR2 SDRAM to 1267MHz with 5-5-5-15 timings.

Vmem was increased to 2.4V in this case. Moreover, we set the DDR Termination Voltage Control at +50mV.

Testbed and Methods

We decided to compare the performance of Gigabyte GA-X38-DQ6 mainboard against that of similar Asus solutions on Intel X38 and Intel P35 chipsets that also use DDR2 SDRAM. To be more exact Gigabyte board will be competing against Asus Maximus Formula and Asus P5K Premium.

The testbeds were built with the following equipment:

Performance in Nominal Mode

The first series of tests were performed with the processor working at its default speed of 3.0GHz set as 9 x 333MHz. The memory frequency in this case was set at 1066MHz with 4-4-4-12 timings.

As usual, we will first check out synthetic benchmarks testing the memory subsystem performance. This parameter is crucial for the performance of mainboards for Intel processors. For our tests we used Lavalys Everest 4.20 utility.

During the memory subsystem performance tests Intel X38 based mainboards run faster than one of the highest-performing Intel P35 solutions. Moreover, Gigabyte GA-X38-DQ6 wins in two most important practical subtests for read speed and latency.

But before we draw any conclusions let’s check out the results of complex benchmarks and real applications.

The results proved up to our expectations. Gigabyte GA-X38-DQ6 mainboard demonstrated very good performance having defeated both competitors in games and during video encoding. However, I have to stress that the performance difference between all three platforms is not significant enough for any of the solutions to claim indisputable leadership. The difference between Gigabyte GA-X38-DQ6 and Asus boards is not more than 1%-2% in most tests.

Performance during Overclocking

Besides the tests in nominal mode, we would also like to compare the mainboards’ performance in overclocked systems. The thing is that relative performance of overclocker platforms is very often different from what we see in nominal mode.

For the second round of tests we decided to set the FSB frequency at 450MHz. We used the same Core 2 Extreme X6850 processor overclocked to 3.6GHz set as 8 x 450MHz. The processor Vcore was increased to 1.45V to ensure better stability. DDR2 memory was running at 1080MHz and the timings were set at 4-4-4-12.

Let’s start with results of synthetic benchmarks:

The situation changes dramatically during overclocking. The memory controller of our Gigabyte GA-X38-DQ6 mainboard didn’t perform very well with the non-nominal FSB frequency. In fact, there is nothing to be surprised with here, as Gigabyte mainboards have always been not very fast in overclocked systems having deserved a few complaints from overclocking fans.

The reasons for this slowness are pretty simple: during overclocking the mainboard BIOS increases the Performance Level latency. As we have already said Asus mainboards set this parameter at 6-7 in the same situation.

However, let’s see how the low memory controller performance will affect the results in real applications and complex benchmarks:

As we have expected, Gigabyte GA-X38-DQ6 yields to its competitors in this case. And the performance difference is no longer that small: in some applications Gigabyte is more than 3% slower than Asus Maximus Formula. This pretty sad result may disappoint some overclocking fans considering Gigabyte GA-X38-DQ6 as their next platform.


Top Gigabyte mainboards used to very rarely receive positive verdict from our lab. From the computer enthusiasts’ prospective, they had a lot of drawbacks that wouldn’t let us recommend them as a good solution for overclocker systems. However, the results of our today’s Gigabyte GA-X38-DQ6 review prove that Gigabyte engineers are working really hard on eliminating former issues.

Gigabyte GA-X38-DQ6 mainboard doesn’t have any problems with powerful processor coolers installation any more, and its BIOS provides easy access to all necessary settings. The only unsolved matter remains the performance drop during overclocking, however, we hope that they will solve this problem in the new BIOS revisions.

All in all, Gigabyte GA-X38-DQ6 made a very good impression on our staff. This board is a worthy option for a high-performance gaming system. It boasts extremely rich specifications and offers excellent and highly functional CPU overclocking tools.

Moreover, this board is compatible with the upcoming Penryn processors, can work with CPUs supporting 1600MHz system bus and supports dual-graphics card Crossfire configurations. Unfortunately, the board doesn’t support the alternative Nvidia SLI technology, but Gigabyte engineers have nothing to do with it: Nvidia doesn’t allow this feature to be supported on any Intel X38 based mainboards.