Do We Really Need Intel X48 Express? - Gigabyte GA-X48T-DQ6 Mainboard Review

by Ilya Gavrichenkov
04/15/2008 | 05:58 AM

The structure of Intel’s core logic solutions available in the market has always been very transparent and clear for the users. Within each chipset generation the company offered a basic discrete core logic set for mainstream systems, its enhanced modifications for high-performance market and a number of integrated models for inexpensive and budget systems. For example, at this time Intel P35 is a basic product, Intel X38 is positioned for the high-end systems, while the whole line-up of integrated solutions, such as G35, G33 and G31, are being offered for the budget segment. However, this well-balanced system we are all so used to may fall apart very soon, because the stores started to offer mainboards on a new core logic set – Intel X48. This product is not intended to simply replace the top Intel X38 chipset, but is positioned at an even higher level than the latter. As a result, the Intel chipset lineup will include not just a solution for enthusiasts – Intel X38, but also a solution for super-extreme enthusiasts – Intel X48.

We first heard the name of the new Intel chipset – X48 Express – last fall. However, it was pretty hard to figure out what would be so different between the new chipset and the Intel X38 one. On the one hand, the formal side to the picture is absolutely transparent. Intel web-site offers a detailed description of the new chipset, which indicates that the only distinguishing feature of the new Intel X48 will be the support of 1600MHz bus and hence DDR3-1600 SDRAM.

But on the other hand, the already existing Intel X38 based mainboards work with processors supporting 1600MHz bus, at this time represented only by one single model - Core 2 Extreme QX9770, without any evident problems. That is why we get the impression that Intel X48 is pretty mach a marketing product that cannot boast any advantages over Intel X38. Besides, Intel X38 and X48 North Bridges are pin-compatible, which backs up this statement additionally. And it means that mainboard manufacturers do not have to develop new mainboard designs and simply install the new core logic set on their already existing products.

However, there is also a different opinion. Some overclockers believe that Intel X48 is an improved solution with higher stability in extreme working conditions. That is why we can often hear that mainboards on the new chipset are more suitable for serious overclocking experiments. They claim that default support of 400MHz front side bus and hence DDR3-1600 SDRAM should ensure better results when the FSB and memory frequencies get raised beyond their nominal values.

So, our today’s article will help figure out what points of view are closer to the truth. Are Intel X48 based mainboards a real overclocker’s dream or the new chipset is just the result of Intel’s marketing efforts? This is the main question we are going to answer today with the help of Gigabyte GA-X48T-DQ6 mainboard based on Intel X48 chipset, which Gigabyte was so kind to provide for our tests.

Accessories Bundle and Specifications

We will start our discussion of the new Gigabyte GA-X48T-DQ6 mainboard features with a picture:

Frankly speaking, the board doesn’t strike you as an absolutely new product. Moreover, the components base and layout of Gigabyte GA-X48T-DQ6 reminds us of the Gigabyte GA-X38T-DQ6 on Intel X38 Express chipset. However, it would be not quite correct if we said that Gigabyte engineers didn’t work on the PCB layout at all. Yes, GA-X48T-DQ6 is very similar to the predecessor, however it features a revised cooling system as well as new processor, memory and PCI Express slots voltage regulator circuitry.

However, you can still find a mainboard with the same PCB layout as GA-X48T-DQ6 among numerous Gigabyte products. It is GA-EX38T-DQ6. Although to be fair, I have to say that it was announced after Gigabyte finished the design of the Intel X48 based solution. In other words, it would be correct to say that Gigabyte has an Intel X38 based solution in its line-up that uses a PCB layout of a more expensive Intel X48 based products, but not the other way around.

Considering that new and old mainboards on different chipsets turned out so close, you will hardly have any questions about the specifications of the new Gigabyte GA-X48T-DQ6.

Although the mainboard specifications are quite ordinary overall, its retail price is expected to be around $300. The reason for that is extremely high price of the new X48 chipset that Intel is currently selling to the mainboard makers for $70 a piece.

The mainboard comes in a traditional package for top Gigabyte products: it is a large golden shimmering box with the board inside and a smaller box with accessories.

Among the goodies are a common user’s manual, a bunch of leaflets and brochures, a CD disk with the software, I/O Shield for the case rear panel, four SATA cables, PATA and FDD cables. Besides, Gigabyte also included two brackets for the case rear panel with the total of four SATA ports and two standard Molex power connectors. Besides, there are also two pairs of cables that allow connecting regular SATA drives to these ports. There is also an additional bonus in the form of two small but extremely useful screws that allow transforming the GA-X48T-DQ6 cooling system from “crazy” into very convenient form.

PCB Design and Functionality

Frankly speaking, we review chapter devoted to peculiarities of the new Gigabyte GA-X48T-DQ6 mainboard could have been left empty. And it would have been absolutely fair to the board as well as to the reader. Since GA-X48T-DQ6 is practically identical to previously released Gigabyte solutions in terms of features as well as specifications, it doesn’t have any unique features to boast. Although there are a few not quite unique features that are still worth discussing here, so we will dwell on them in this part of our review. However, if you are very well familiar with Gigabyte mainboards on Intel X38 chipset, you can actually skip this section and move on to the next one.

First of all, I would like to say that Gigabyte GA-X48T-DQ6 is designed for dual-channel DDR3 SDRAM that can ensure better performance these days, especially during overclocking. This is the default memory type for Intel X48, but some manufacturers, including Gigabyte, also offer similar solutions with DDR2 DIMM slots, since this chipset, just like its predecessors boasts a universal memory controller. The set of supported dividers for memory frequency is also standard on GA-X48T-DQ6. So this mainboard, just like other mainboards on Intel’s “third series chipsets”, cannot clock the memory at any frequency that is more than twice as high as the FSB frequency. That is why the promised support of DDR3-1900 SDRAM that is posted on the mainboard box as well as Gigabyte’s company web-site is simply a marketing trick. In reality, this memory frequency can be achieved only if you overclock the FSB to 475MHz.

Since Gigabyte GA-X48T-DQ6 is positioned as a top of the line solution, it features two fully-functional PCI Express x16 slots compliant with 2.0 specification. These slots allow installing two graphics cards combined into a single Crossfire configuration. I would like to specifically point out that the graphics slots have been very conveniently located on the PCB. There is a significant gap between them, which will be enough for any cooling system. The remaining PCI and PCI Express x1 expansion slots will never be fully blocked in this case.

The chipset cooling system called Silent Pipe uses heatpipes and is designed according to pretty common contemporary schematics. One heatpipe connects a small heatsink on top of the chipset South Bridge with the heatsink on the chipset North Bridge. Another two heatpipes originate from the North Bridge heatsink and lead to the heatsink on processor voltage regulator MOSFET. However, some transistors from the CPU voltage regulator circuitry located above the LGA775 socket didn’t get under the Silent Pipe cooling system and are topped with individual miniature heatsink. However, you shouldn’t worry about it because they do not warm up that much during work. Moreover, the heatsink on the main MOSFET serves mainly not to cool down the processor voltage regulator, but to dissipate the heat generated by the chipset North Bridge and transferred from it via heatpipes.

Although the above described cooling system seems to be a pretty ordinary one, it is extremely efficient. The primary reason for that is the use of solid copper for heatpipes and heatsinks. They also paid special attention to ensuring proper contact between the heatsinks and the chips: they are all attached with spring screws. And finally, Gigabyte engineers ensured proper heat dissipation at the bottom of the PCB by placing a low-profile aluminum Crazy Cool heatsink plate right beneath the hot mainboard components.

However, as we have already pointed out in our previous articles, this heatsink may prevent you from installing some processor coolers properly, that is why you may need to remove it. It is great that Gigabyte GA-X48T-DQ6 allows doing it without any problems at all.

To implement some of the features the developers used a number of additional controllers. The mainboard is equipped with an IEEE1394 controller from Texas Instruments; two Realtek RTL8111B Gigabit network controllers that can work in Teaming mode; an additional Gigabyte SATA2 Serial ATA RAID controller supporting two additional ATA_300 and one PATA-133 ports. As a result, Gigabyte GA-X48T-DQ6 allows connecting very diverse additional devices. However, despite quite numerous connectors and chips on the mainboard PCB, it doesn’t cause any trouble during system assembly.

I believe that pretty much the only serious inconvenience is the fact that Clear CMOS contacts are located between the PCI Express x16 slots, right next to the battery. It will be really hard to reach them inside an assembled system with both graphics cards installed. Luckily, contemporary BIOS versions do not require frequent use of Clear CMOS, so this drawback is very unlikely to spoil the overall positive impression from Gigabyte GA-X48T-DQ6 mainboard. Especially, since all other connectors and pin-connectors have been arranged in a very smart manner: mostly along the lower edge of the PCB. You can see two connectors for four USB 2.0 ports, a connector for IEEE1394 port and even the connectors for COM and LPT that are close to oblivion these days. In the corner you can see six Serial ATA connectors, four provides by the ICH9R South Bridge and the remaining two, of different color, by the Gigabyte SATA2 additional onboard controller. The same controller is responsible for the PATA connector located nearby that has been conveniently turned parallel to the board. Another pair of SATA ports implemented via the chipset South Bridge is placed a little higher.

GA-X48T-DQ6 also supports FDD: the FDD pin-connector can be found to the right of the DIMM slots.

There is quite a lot of free room around the processor socket. Most super-coolers fit onto this mainboard easily. There are only two cases when you may encounter problems during cooler installation: if you are using memory modules of non-standard height or if the power supply panel of your system case is very close to the top edge of the mainboard PCB. The thing is that LGA775 socket on GA-X48T-DQ6 has been moved relatively close to DIMM slots and to the upper PCB edge, so please, keep this in mind.

The mainboard back panel also leaves a highly favorable impression. It bears a very diverse set of ports and connectors. There are eight USB 2.0 ports, two different IEEE1394 ports, two Gigabit network ports, PS/2 connectors for keyboard and mouse, optical and coaxial SPDIF outs and six analogue audio-jacks.

By the way, the integrated sound on GA-X48T-DQ6 uses an eight-channel Realtek ALC889A codec with the specified signal-to-noise ratio of 106dBA. I would like to point out that this codec supports DTS Connect technology that delivers multi-channel digital sound stream via digital audio-outs on the mainboard if there is an external compatible receiver available.

Processor Voltage Regulator Circuitry and DES

We put the discussion of the GA-X48T-DQ6 processor voltage regulator circuitry into a separate section on purpose. The thing is that even though it seems at first glance that this mainboard uses a traditional six-phase processor voltage regulator, typical of top Gigabyte mainboards, it is in fact completely different from the predecessors. This board’s processor voltage regulator circuitry, just like the one on a few other new solutions from the same manufacturer, supports DES (Dynamic Energy Saver) technology that should additionally reduce the processor power consumption with a few skillful tricks.

The schematics of the GA-X48T-DQ6 voltage regulator are pretty standard. It is based on Intersil ISL6327 micro-chip that Gigabyte has been using in its mainboards for a long time already. Six-phase regulator is built with high-frequency power MOSFET, which ensures not only longer life but also higher efficiency and lower operational temperature. Besides, they use highly reliable high-quality Japanese capacitors with polymer electrolyte for the voltage regulator as well as on the rest of the board. It is pretty funny that Gigabyte’s marking people are still trying to present the voltage regulator as a 12-phase one referring to twice as many inductance coils. But, don’t buy into it.

The main distinguishing feature of this voltage regulator is its ability to switch the number of active phases during work thanks to the ISL6327 functions. This is how Gigabyte is going to ensure that their mainboard will be more economical from the power consumption standpoint. The thing is that it makes sense to use more phases for a processor voltage regulator only if the power consumption is high: in this case six-phase circuitry will be more efficient and reliable and will generate higher quality signal. It is not economical to use a lot of phases under low workload as they may eat up more power. These are the reasons that drove Gigabyte engineers to design a circuitry with variable number of active phases: from 2 to 6.

The same concept is also implemented on ASUS mainboards, however they allow switching only between 4 to 8 phases. Gigabyte promises higher efficiency thanks to five different circuitry statuses. However, this is not the only difference between ASUS and Gigabyte approaches. While ASUS offers a fully hardware solution that doesn’t require any special software, Gigabyte’s circuitry works only when you launch Dynamic Energy Saver Utility. This utility monitors processor power consumption and uses this data to adjust the number of active phases in the processor voltage regulator in real time. If it is not launched, the regulator will work according to traditional six-phase algorithm.

The information window of the Dynamic Energy Saver Utility provides the user with data on the current processor power consumption, number of active phases and the actual energy savings statistics. I would like to add that you can also see how many phases of the CPU voltage regulator are active from the row of multi-color LEDs on the mainboard PCB located to the right from DIMM slots.

Besides the phase switching within processor voltage regulator circuitry, Dynamic Energy Saver Utility also does a few other things aimed at saving even more power. Firstly, this utility reduces the processor Vcore by 0.05-0.08V. There is a CPU Voltage Level switch that determines how greatly the Vcore will be lowered; however, unfortunately, you cannot skip it completely. Secondly, this utility can also enable processor throttling if you want to, so that the CPU will skip every other clock cycle under low workload.

As a result, we can conclude that DES technology first of all saves power in idle mode. In case of full CPU utilization, throttling will be disabled and the voltage regulator will activate all six channels. The only way to save power in this case is the forced lowering of the processor core voltage, which is more of a trick than an engineering approach.

To prove everything we have just said, we measured the power consumption of a quad-core Core 2 Extreme QX9770 processor in case of different DES settings. Enhanced Intel SpeedStep was activated.

As we see, DES technology does reduce the processor power consumption and power losses in the voltage regulator circuitry. The obtained results prove this statement with all certainty. But do not forget that the mainboard drops the CPU Vcore below the nominal value, which may lead to potential loss of system stability and overall, can hardly be considered a technologically fair approach. The same thing can actually be done on any mainboard that allows manual adjustment of the processor Vcore parameter. Unfortunately, it is impossible to estimate how efficient changing the number of active phases in the processor voltage regulator circuitry in real time actually is, because once DES is launched, the processor Vcore inevitably drops.

So, the current DES version is pretty interesting from the theoretical prospective, but its practical implementation still arouses a number of serious questions. Firstly, the processor Vcore drops below the nominal regardless of the user’s wishes. Secondly, DES requires installation and non-stop operation of a special utility. And thirdly, this technology doesn’t work with overclocked processors.

In other words, DES will hardly be of interest to computer enthusiasts at this time. at least until Gigabyte engineers make a few changes to it.

BIOS Functionality

Gigabyte GA-X48T-DQ6 mainboard was tested with BIOS version F4 dating back to March 6, 2008.

BIOS Setup interface of Gigabyte GA-X48T-DQ6 mainboard is very similar to that of some other Gigabyte mainboards released recently. And it is actually not surprising at all, the developers created their brand name style, put everything together for maximum user comfort, gave up “hidden” options, added all necessary utilities and now the Gigabyte BIOS Setup became very functional, simple and easy to work with.

Almost all the options dealing with major system parameters configuration are gathered in a special BIOS section called MB Intelligent Tweaker (M.I.T.). This particular section will be of primary interest to overclocking fans.

Here you can set the processor multiplier and FSB frequency from 100 to 700MHz with 1MHz increment. You can also adjust dynamic CPU overclocking depending on its utilization using C.I.A.2 technology. Note that the BIOS supports 45nm processors and allows changing the multiplier setting with 0.5x increment.

BIOS Setup of Gigabyte GA-X48T-DQ6 also offers a technology for automatic graphics card overclocking called Robust Graphics Booster.

The memory subsystem frequency is set with special dividers: just like on the solutions using previous generation Intel chipsets. Gigabyte GA-X48T-DQ6 offers a complete set of FSB:Mem coefficients for Intel X48. Note that you also set FSB Strap frequency together with the divider. It is represented as a remark to each divider in the corresponding menu. It is nice to see the current and set memory frequency displayed right next to the FSB:Mem setting option, which makes configuring it a lot easier.

There is Performance Enhance menu right next to the option for DDR3 SDRAM frequency setting. You can choose one of the following: Standard, Turbo and Extreme. This option affects the major chipset speed parameter, a latency called Performance Level. However, you should remember that it only works if the memory timings are configured automatically.

Gigabyte GA-X48T-DQ6 BIOS allows adjusting the following memory latencies:

When you configure the settings, the mainboard displays all parameter values and allows setting any of them to Auto, which makes it a lot easier for inexperienced users to work with the BIOS Setup.

I would also like to point out that Static T_READ Value parameter has no direct connection with the memory timings. This is what Gigabyte mainboards BIOS calls the Performance Level, which sets the latency for the chipset North Bridge used to synchronize the FSB and memory bus frequencies. In other words, GA-X48T-DQ6 allows advanced users to adjust Performance Level manually, which makes this board an ideal solution for overclocking.

As for the voltage adjustment, the board supported the following settings:

All voltage settings except processor Vcore are provided as relative values. Actual voltages can only be set for the CPU. There is a very convenient information field showing the default Vcore of the system processor right next to it.

Besides everything we have already mentioned, Gigabyte also offers Loadline Calibration option that allows reducing the drop of the CPU Vcore under heavy workload. For example, when we overclocked quad-core Core 2 Extreme QX9770 processor to 4.0GHz by raising its Vcore to 1.4V, Vdroop on our board reached 0.088V under maximum workload and 0.04V in idle mode. Enabling Loadline Calibration helped ensure lower voltage drop of 0.056V and 0.024V respectively. I can’t say that it is a good result, but it is still better than nothing. Especially since in the past Gigabyte engineers used to disregard this useful option completely.

Besides the most important overclocking-friendly MB Intelligent Tweaker (M.I.T.) section, there are a few other pages of the BIOS Setup worth your close look.

 For example, PC Health Status page where hardware monitoring functions are concentrated.

Note that the board allows adjusting the rotation speed of the processor fan depending on the CPU temperature.

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

Gigabyte engineers also made sure that you can save your settings profiles. The board allows saving up to 8 profiles. All profiles when the board booted successfully will be saved automatically.

When you overclock, the board normally doesn’t require using Clear CMOS jumper. If it cannot restart after you changed some of the settings, the MB Intelligent Tweaker (M.I.T.) settings get reset to defaults. However, unfortunately, the user received no notification about it and the board simply continues booting with non-optimized parameters.

Also, GA-X48T-DQ6 boasts a built-in Q-Flash utility that allows updating the BIOS without booting the OS.

Moreover, Gigabyte GA-X48T-DQ6 mainboard supports Dual BIOS technology. Therefore, there is an additional Flash memory chip with a BIOS copy on the mainboard PCB that will save the day if the main BIOS dies.

Overclocking Experiments

You have every right to expect mainboards on Intel X48 chipset to be a little better at CPU overclocking than their predecessors. Since this chipset supports higher FSB speeds, up to 400MHz, in nominal mode. However, only practical experiments will show if this is true or not.

 To check out the overclocking potential of the new Gigabyte GA-X48T-DQ6 mainboard we put together a special testbed that included the board, of course, 2GB DDR3-1800 from Cell Shock (CS3222580), OCZ GeForce 8800GTX graphics card, Western Digital Raptor WD1500AHFD HDD and SilverStone SST-ST85ZF power supply unit. The CPU was cooled with Scythe Infinity cooler.

First of all, we decided to determine the maximum FSB frequency when the mainboard would run stably with a dual-core processor. We used a 45nm Core 2 Duo E8500 with 3.16GHz nominal speed (9.5 x 333MHz). The stability was checked with a standard one-hour run of OCCT Perestroika 2.0.0a application.

Practical experiments showed that our system can run stably with a dual-core CPU at 450MHz FSB without any special tricks on our end. If the CPU and the memory can work in this mode the mainboard will definitely support it. You won’t even have to increase the North Bridge voltage.

When the CPU clock frequency multiplier is lowered to 8x, we could hit a more important psychological maximum of 500MHz. However, in this case we had to push the FSB and North Bridge voltages 0.3V up to ensure stability of our test system.

The record-breaking FSB frequency with a dual-core processor overclocked on GA-X48T-DQ6 mainboard equaled 525MHz. It was achieved by raising the FSB voltage 0.35V higher and increasing the North Bridge voltage by 0.4V at the same time.

In this case the system remained absolutely stable. The CPU worked at 4.2GHz frequency with Vcore set at 1.4V. Memory ran with 1.9V voltage setting and 7-7-7-20 timings at 1680MHz.

I would like to say that if you use different dividers to set the DDR3 SDRAM frequency at a lower value, the workload on the chipset North Bridge will reduce dramatically. As a result, you will be able to achieve system stability without any significant NB voltage increase. In our case when the FSB:DRAM multiplier was set at 5:8, we had to resort to one more trick to ensure stability: we manually raised Static T_READ Value (Performance Level) to 12, which has some negative effect on the memory subsystem performance.

So, it is not quite correct to claim that mainboards based on the new Intel X48 chipset boast significantly higher FSB overclocking potential than those on Intel X38. However, we may be able to reveal certain improvements during quad-core processors overclocking. Let’s check it out now. For the next round of experiments we upgraded the above described testbed based on Gigabyte GA-X48T-DQ6 mainboard with a Core 2 Quad Q9300 processor from the Penryn family that works at the nominal speed of 2.5GHz (7.5 x 333MHz).

As we know, quad-core processors overclocking by raising the FSB frequency stumbles upon first problems much sooner than dual-core processors overclocking. That is why it is not surprising that we had to really fine tune the BIOS parameters to ensure that our GA-X48T-DQ6 will run stably at 450MHz FSB with Core 2 Quad Q9300 processor. To pass the stability tests we had to increase the FSB voltage to its maximum, i.e. by 0.35V, while the NB voltage was set 0.25V higher. Only with these settings Core 2 Quad Q9300 remained stable at 3.37GHz frequency.

Further overclocking was even harder to perform. To get our testbed to work at 460MHz FSB, the chipset North Bridge voltage had to be set 0.3V higher. And at 470MHz FSN the system stopped booting the OS with any settings.

As a result, the maximum overclocking for a quad-core Core 2 Quad Q9300 processor on Gigabyte GA-X48T-DQ6 mainboard was the modest 3.45GHz frequency.

So, looks like Intel X48 chipset used for Gigabyte GA-X48T-DQ6 mainboard failed to improve quad-core CPU overclocking. You can get pretty much the same results for quad-core CPUs on older mainboards using Intel X38 or even Intel P35 chipsets.

Benchmark Results

We compared the performance of Gigabyte GA-X48T-DQ6 mainboard on the new Intel X48 chipset against that of widely spread platforms on Intel X38. Since GA-X48T-DQ6 supports DDR3 SDRAM, we selected ASUS P5E3 Deluxe to be its main competitor in this test session.

Testbeds were configured as follows:

• CPU: Intel Core 2 Duo E8500 ((LGA775, 3.16GHz, 1333MHz FSB, 6MB L2, Wolfdale).
• Mainboards:
  • ASUS P5E3 Deluxe (LGA775, Intel X38, DDR3 SDRAM);
  • Gigabyte GA-X48T-DQ6 (LGA775, Intel X48, DDR3 SDRAM).
• Graphics card: OCZ GeForce 8800GTX (PCI-E x16).
• HDD: Western Digital WD1500AHFD (SATA150).
• OS: Microsoft Windows Vista x86.

Performance in Nominal Mode

The first series of tests were performed with the processor working at its default speed of 3.16GHz set as 9.5 x 333MHz. The memory frequency in this case was set at 1333MHz with 7-7-7-20 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 4.50 utility.

Although we made sure that primary timings, Command Rate and Performance Level were the same on both test platforms, ASUS and Gigabyte mainboards configured secondary timings differently, which led to different results of the memory subsystem tests. Nevertheless, even now we can already state that Intel X48 cannot ensure higher performance than Intel X38. The memory controller in Intel’s “third series” chipsets is so well optimized that there is simply no room left for further improvement. That is why we can only expect Intel based platforms to demonstrate any performance growth when they launch new Nehalem processors with principally new memory controller built into the CPU core.

However, before we make any final conclusions, let’s check out the situation in complex benchmarks and real applications.

The results indicate that in most cases Gigabyte GA-X48T-DQ6 outperforms ASUS P5E3 Deluxe. However, don’t get too excited just yet. The thing is that it is not the superiority of the new Intel X48 chipset over Intel X38, but the fact that Gigabyte mainboard doesn’t set the nominal FSB frequency quite fairly using 335MHz instead of 333MHz.

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 Duo X8500 processor overclocked to 4.275GHz set as 9.5 x 450MHz. The processor Vcore was increased to 1.4V to ensure better stability.

DDR3 memory was running at 1800MHz and the timings were set at 8-7-7-20.

During our overclocking experiments with Gigabyte GA-X48T-DQ6 we discovered one very interesting thing. In the above described test mode, this mainboard automatically sets Performance Level to 7 while ASUS P5E3 Deluxe uses default Performance Level = 8.

Gigabyte GA-X48T-DQ6

ASUS P5E3 Deluxe

This could be the shaky advantage of Intel X48 over Intel X38: newer chipset can work with lower Performance Level settings. However, you can make ASUS P5E3 Deluxe work with Performance Level = 7, although you will have to increase the NB voltage quite noticeably in this case to ensure stability: from the default 1.25V to 1.7V. Gigabyte GA-X48T-DQ6 supports Performance Level 7 at 450MHz FSB and default NB voltage.

Unfortunately, even increased NB voltage didn’t help get Gigabyte GA-X48T-DQ6 to work with Performance Level 6. Therefore, we compared the performance of our testing participants’ with FSB overclocked to 450MHz in two modes for ASUS P5E3 Deluxe and only in one mode for Gigabyte GA-X48T-DQ6.

Let’s start with synthetics:

As we see, Performance Level parameter is not a determinative here although it does indeed have a serious effect on the results. As you can see, ASUS P5E3 Deluxe outperforms Gigabyte GA-X48T-DQ6 in read speed and latencies even with higher Performance Level setting. However, despite this fact we can’t help pointing out significant improvement: unlike previous Gigabyte’s solutions, GA-X48T-DQ6 doesn’t increase Performance Level during overclocking and demonstrates quite acceptable results.

Let’s check out the results obtained in complex tests and real applications:

The numbers speak for themselves. Overclocked Gigabyte GA-X48T-DQ6 shows very good speed in real applications. From the performance prospective, it can compete successfully against ASUS P5E3 Deluxe even with manually lowered Performance Level.

Conclusion

It turns out that despite mainboard makers’ desires, Intel X48 based solutions cannot be regarded as really new products. The chipset doesn’t boast any significant advantages over Intel X38. as for the 1600MHz bus support that has been formally introduced in the new Intel X48, it is a pure marketing trick, since even older mainboards on Intel X38 can work just fine with the only CPU supporting this bus – Core 2 Extreme QX9770.

Moreover, Intel X48 features the same memory controller as Intel X38. It means that mainboards based on these two chipsets will only differ due to settings in the BIOS Setup of particular mainboards. Don’t expect new boards to work any overclocking wonders. According to our tests, maximum FSB frequencies during overclocking depend on the PCB layout and processor overclocking potential and not on the chipset. The only arguable advantage of the new Intel X48 that we still need to investigate more in our upcoming articles is the more flexible Performance Level adjustment, which may potentially ensure better performance of mainboards based on this core logic set.

Nevertheless, Intel X48 Express based mainboards are worth your attention since in most cases they are better finalized and enhanced modifications of the previous generation boards on Intel X38. Although, you will have to pay the price, as these solutions cost considerably more than their predecessors.

Everything we have just said is true for the particular mainboard we discussed today – Gigabyte GA-X48T-DQ6. In fact, this solution is not very much different from Gigabyte Intel X38 based products that have been available in the market for a while. The main improvements include redesigned processor voltage regulator circuitry with DES technology and better BIOS optimization. And while the new “economical” voltage regulator may not be very the practical yet for computer enthusiasts, the BIOS of the new GA-X48T-DQ6 is definitely a significant step forward and Gigabyte engineers surely have to be given proper credit for that. The biggest advantage of the new mainboard’s BIOS is no performance drop during overclocking that was so frustrating for many overclocking fans who used to work with Gigabyte platforms in the past.

As a result, Gigabyte GA-X48T-DQ6 can be considered a very good choice for a high-end system.