"Expectation is the root of all heartache."

This quote by noted playwright William Shakespeare expresses our opinion about the Intel D975XBX. Although motherboards from Intel have generally been designed and offered for the business, education, or home office user, they have been directing their efforts towards the enthusiast market recently. In fact, Intel has loosened their white collars and taken off the blue suits with the introduction of the Extreme Series product line last year. Well, that might be an overstatement when compared to other enthusiast product offerings based on Intel chipsets, but Intel does recognize the importance of the gaming and advanced user in the marketplace.

The Intel D975XBX, code name Bad Axe, is a follow-up to the Intel D955XBK, which was based on the Intel 955x chipset. The Extreme Series product line includes the Intel D955XBK, Intel D955XCS, and the Intel D975XBX at this time. This product series is a departure for Intel as mentioned earlier and is geared towards the Intel power-user and high-end gamer while maintaining the exceptional security and stability of Intel's desktop board solutions.

The chart above lists the standard feature set available when utilizing the Intel 82975X chipset. The Intel 975X Express Chipset enables full support for two PCI Express x8 slots for multi-view or GPU capability, ATI CrossFire technology, Intel Memory Pipeline Technology (MPT), Intel Flex Memory Technology, 8GB memory addressability, and ECC memory support.

The Intel MPT is enhanced over the 955X iteration to offer improved pipelining to enable a higher utilization of each memory channel, resulting in better performance through increased transfers between the processor and system memory. Intel Flex Memory Technology allows different memory sizes to be populated and still remain in dual-channel mode.

The new architecture also supports both asynchronous and isochronous data traffic, with dedicated internal pipelines and specialized arbitration. In addition, the 975X chipset has improved electricals with optimized ball-out for better latency compared to the 955X chipset. We noticed small, but not significant improvements in our test results.

Intel chose to augment this feature set with additional SATA capabilities via the Silicon Image SiI 3114 chipset, and Firewire 1394a support via the TI TSB43AB23 chipset.

Let's find out if the board met our expectations or left us with heartache.



Basic Features: Intel D975XBX

Specification	Intel D975XBX
CPU Interface	LGA775-based Pentium 4, Pentium 4 XE, Celeron D, and Pentium D processors
Chipset	Intel 975X - MCH ICH7R - ICH
Pentium D Support	820D, 830D, 840D, 840EE, 920D, 930D ,940D ,950D , 955EE
Front Side Bus	1333 / 1067 / 800 / 533 MHz
Host Burn-In Mode	0 - 30% (in 1 percent increments)
Memory Speeds	Default, DDR-2 333, 400, 533, 667, and 800MHz
PCI Bus Speeds	Default, 40.00MHz
PCI Express Bus Speeds	Default, 101.32, 102.64, 103.96, 105.28, 106.6, 107.92, 109.24MHz
Set Processor Multiplier	12 to 40, (in 1 step increments)
Core Voltage	Default, 1.2750V to 1.6000V (in 0.0125V increments)
DRAM Voltage	Default, 1.80V, 1.90V, 2.00V, 2.10V, 2.20V
MCH Chipset Voltage	Default, 1.525V, 1.600V, 1.650V, 1.725V
FSB Termination Voltage	Default, 1.271V, 1.333V, 1.395V
Memory Slots	(4) x DIMM, max. 8GB, DDR2 667/533/400, non-ECC, ECC, un-buffered memory
Expansion Slots	(2) x PCI-E x16 (operates in 1x16 and 1x8 or 2x8 mode) (1) x PCI-E x16 (operates in x4 mode) (2) x PCI 2.3
Onboard SATA	Intel ICH7R: (4) x SATA 3Gb/s
Onboard IDE	Intel ICH7R: (1) x UltraDMA 100/66/33
SATA/IDE RAID	Intel ICH7R: (4) x SATA 3Gb/s RAID 0, RAID 1, RAID 5, RAID 10, and Intel Matrix Storage technology Silicon Image SiI 3114: (4) x SATA 1.5Gb/s RAID 0, RAID 1, RAID 0+1 (operates on PCI bus)
Onboard USB 2.0/IEEE-1394	(8) USB2.0 ports (2) IEEE 1394a FireWire Ports by TI TSB43AB23
Onboard LAN	Intel 82573L PCI-E x1 Gb LAN
Onboard Audio	Sigmatel STAC9221D, 8-channel capable HD Audio Codec featuring Dolby Master Studio technology
Power Connectors	24-pin ATX 4-pin 12V Plug 8-pin EATX 12V
Back Panel I/O Ports	1 x PS/2 Keyboard 1 x PS/2 Mouse 1 x Parallel 1 x Serial 1 x Audio I/O Panel 1 x Optical S/PDIF Out Port 1 x Coaxial S/PDIF Out Port 1 x RJ45 4 x USB
Other Features	Value Added Software: Intel® Audio Studio Intel® Desktop Utilities Intel® Desktop Control Center InterVideo* WinDVD* Ulead* VideoStudio* 9 SE DVD InterVideo* MediaOne* Gold Musicmatch* Jukebox Farstone RestoreIT!* Gold Farstone Gamedrive* Norton* Internet Security Norton* AntiVirus Yahoo!* Toolbar with Anti-spy
BIOS	Intel 0420 (01/05/2006)

The Intel D975XBX is a member of the Extreme Series product family and, as such, is a fully featured flagship board targeted towards the Intel enthusiast. The board ships with an extensive accessory package that includes a 3.5" front panel bay for audio, IEEE1394, and USB 2.0 connections. Intel also includes several desktop utilities for monitoring and tuning your system.

This is the main BIOS screen and displays the generic options available on the board.

The advanced BIOS section allows you to view or change the majority of the system settings.

The advanced screen allows you to set individual parameters for voltage, multipliers, and chipset settings. You must first answer "yes" to the standard legal verbiage before being allowed to modify the limited range of settings. The Host Burn-In Mode Type option allows you to set a positive or negative value when determining whether to increase or decrease the front side bus. The Host Burn-In Mode Percentage option allows you to increase the front side bus up to 30% in 1% increments.

The board fully supports manual memory timing adjustments or allows for a Default setting that will set the memory to the SPD settings. The memory voltage settings have been increased to 2.2V.

Overall, the BIOS options are sparse on the Intel D975X compared to other enthusiast boards, with memory voltage to 2.2V, and a limited range of chipset, bus, and vCore voltage adjustments. However, the support for a 1333 FSB is interesting at this time. The BIOS will not recover by itself if you choose an incorrect setting. You will need to power down the system, switch the BIOS configuration jumper, power on the system, make the necessary changes in the BIOS, power down the system, switch the BIOS configuration jumper, and then power on the system. We cannot understand why Intel continues to require this interaction on their enthusiast board as it can become very frustrating while exploring the performance abilities of varied components.



INTEL D975XBX: Features

Intel designed a very well laid out board with all major connections easily reached. The board is lacking most clearance issues and was simple to install in a mid-size ATX case. The board features a 5-phase voltage regulator power design that contributed to excellent stability. The MOFSETS are now passively cooled via decorative heat sinks that certainly offer additional stability over the prior Intel D955XBK board that was a 4-phase design with inadequate cooling around the CPU area.

The DIMM module slots' color coordination is correct for dual channel setup. The memory modules are simple to install with a full size video card placed in the first PCI Express x16 slot. The power plug placement favors standard ATX case design and the power cable management is very good. The floppy drive port connector is conveniently located on the edge of the board along with the 24-pin ATX power connector.

The Intel ICH7R IDE port connector is located on the edge of the board and did not present any connection issues in our mid-size ATX case.

The Intel SATA ports are conveniently located below the ICH7R chipset and to the left of the primary IDE connector. The SATA ports feature the new clamp and latch design. Unlike other 975x boards, the SATA ports are not color-coded for primary and secondary operation. We found the positioning of the SATA ports to be excellent when utilizing the ATI CrossFire cards in the primary and secondary PCI Express connectors.

The Silicon Image SiI 3114 SATA RAID port connectors are clustered on the left edge of the board. The Intel USB connectors and chassis panel are located below the SiI 3114 port connectors and to the left of the Intel SATA port connectors. The BIOS configuration jumper block is a traditional jumper design located above the IDE port connector. The location of this jumper was acceptable during repeated usage.

The board comes with (3) physical PCI Express x16 connectors and (2) PCI 2.3 connectors. The layout of this design offers a good balance of slots and allows for additional add-in peripheral cards.

The first physical x16 connector located next to the MCH heat sink is the primary PCI Express connector and is set up for electrical routing in x16 or x8 operation. The x16 interface supports full duplex transfers up to 8 GBytes/second in x16 operation and single-ended transfers are supported up to 4 GBytes/second in x8 operation.

The next physical x16 connector is the secondary PCI Express connector and is set up for electrical routing in x8 operation. This connector also fully supports x4 and x1 PCI Express add-in cards. The final physical x16 connector is set up for electrical routing in x4 operation and fully supports x4 or x1 PCI Express add-in cards.

We did not have any issues installing an ATI X850 Crossfire Edition setup in the primary and secondary x16 PCI Express slots. This configuration will physically render the first PCI slot useless. There were no issues utilizing this slot with video cards containing single slot cooling systems.

Returning to the CPU socket area, we find ample room for alternative cooling solutions. We utilized the stock Intel heat sink, but also verified several aftermarket cooling systems such as the Thermaltake Big Typhoon would fit in this area during our tests. However, due to the large MCH heat sink and the MOFSET heat sinks, installation of large air or water cooling solutions could be problematic. While the MOFSET heat sinks are decorative and provide additional cooling, they did present issues when changing out heat sinks due to their height and proximity to the mounting holes.

The MCH and ICH chipsets are passively cooled with heat sinks that do not interfere with any installed peripherals. In fact, this system kept the chipsets cool enough that additional chipset voltage was not a factor in our overclocking tests. Intel places the eight-pin 12V auxiliary power connector at the top of the CPU socket area, but out of the way of most aftermarket cooling solutions. However, the 4-pin auxiliary power connector is located in a difficult position and can hamper airflow with cabling that crosses over the heat sink.

The rear panel contains the standard PS/2 mouse and keyboard ports, parallel port, serial port, LAN port, and 4 USB ports. Located below the parallel port and to the right of the serial port is the Coaxial S/PDIF port. The LAN (RJ-45) port has two LED indicators representing Activity and Speed of the connection. The audio panel consists of 5 ports that can be configured for 2, 4, 6, and 8-channel audio connections along with the Optical S/PDIF port.



FSB Overclocking Results

Front Side Bus Overclocking Testbed
Processor:	Pentium 4 Smithfield LGA 775 840EE Dual Core 3.2GHz
CPU Voltage:	1.5125V (1.4000V default)
Memory Settings:	3-2-2-8 at 667MHz
Memory Voltage:	2.2V
MCH Voltage:	1.60V
ICH Voltage:	Default
Cooling:	Thermaltake Big Typhoon
Power Supply:	OCZ Power Stream 520
Maximum CPU OverClock:	200fsb x 20 (4000MHz) +25%
Maximum FSB OverClock:	260fsb x 15 (3900MHz) +30%

This board is a decent overclocker considering the limited settings available in the BIOS. At these overclock settings, the system was able to complete all of our benchmark test suites three consecutive times and run Prime95 and SuperPI without issue. We were able to overclock the FSB to 260 at the 16x multiplier, which resulted in CPU operation of 4160MHz, but we could not complete our test suite. We also were able to raise the CPU multiplier to 21 at the 200 FSB setting, which resulted in the CPU operation of 4200MHz, but it could not run any tests reliably.

We tried two other boards, but we did not have success in increasing the CPU multiplier past 20 or utilizing a combination of the CPU multiplier and the FSB frequency override setting past the reported numbers. Even though this particular CPU has reached 4.4GHz, we could not pass the 4.0GHz mark and maintain stability or complete our test suite. We will be receiving a retail board shortly and will re-examine the overclocking ability of the board with our 840EE, 950D, and 955EE processors.

Memory Stress Testing

Memory stress tests look at the ability of the Intel D975XBX to operate at the officially supported memory frequencies of 667MHz DDR2, at the best performing memory timings that the Corsair CM2X512A-5400UL revision 1.3 will support.

Intel D975XBX Stable DDR667 Timings - 2 DIMMs (2/4 slots populated - 1 Dual-Channel Bank)
Clock Speed:	200MHz (800FSB)
Timing Mode:	667MHz - Default
CAS Latency:	3
RAS to CAS Delay:	2
RAS Precharge:	2
RAS Cycle Time:	8
Voltage:	2.1V

The Intel D975XBX was very stable with 2 DDR2 modules in Dual-Channel at the settings of 3-2-2-8 at 2.1V. We will now install all four available memory slots that are usually more strenuous on the memory subsystem than testing 2 DDR2 modules on a motherboard.

Intel D975XBX Stable DDR667 Timings - 4 DIMMs (4/4 slots populated - 2 Dual-Channel Banks)
Clock Speed:	200MHz (800FSB)
Timing Mode:	667MHz - Default
CAS Latency:	4
RAS to CAS Delay:	2
RAS Precharge:	3
RAS Cycle Time:	8
Voltage:	2.2V

The Intel D975XBX was completely stable with 4 DDR2 modules in Dual-Channel at the settings of 4-2-3-8 and needed the voltage increased to 2.2V. We tried several combinations of memory settings at the CAS Latency of 3, but the board was not stable enough to complete our test suite. This is the first i975x board that we have tested that did not allow a CAS Latency of 3 in our testing with 4 DDR2 modules.



Test Setup

The Intel 975X chipset fully supports all dual core Pentium D processors in both stock and overclocked conditions. This chipset also supports the upcoming Cedar Mill processor range. Dual core really makes a difference in certain multi-tasking scenarios, as was demonstrated in the dual core performance preview. If you are interested in how the various chipsets perform in a real world multitasking setup, please take another look at that review.

Performance Test Configuration
Processor(s):	Intel Pentium 840EE (3.2GHz, 800FSB, Dual-Core, 2x1MB L2, HT) utilized for all tests
RAM:	2 x 512MB Corsair CM2X512A-5400UL revision 1.3 Settings- DDR2-667 as noted at (CL3-2-2-8)
Hard Drive(s):	2 x Maxtor MaXLine III 7L300S0 300GB 7200 RPM SATA (16MB Buffer), 1 x Maxtor MaXLine III 7L300R0 300GB 7200 RPM IDE (16MB Buffer)
System Platform Drivers:	Intel Chipset Software - 7.2.2.1006 NVIDIA Platform Driver - 6.82
Video Cards:	1 x XFX 7800GTX OC (PCI Express) for all tests
Video Drivers:	NVIDIA nForce 81.98 WHQL
Cooling:	Thermaltake Big Typhoon
Power Supply:	OCZ Power Stream 520
Operating System(s):	Windows XP Professional SP2
Motherboards:	Intel D975XBX Asus P5WD2-E Asus P5N32-SLI Deluxe Gigabyte GA-G1 975X Asus P5WDG2-WS

General Performance & Encoding

The Intel D975XBX performance is below that of all other boards. However, the differences between the Intel 975X boards are reasonable with the nForce4 providing excellent scores in this series of benchmarks. Based upon the history of Intel's BIOS releases, we can expect additional performance from this board.




Memory Performance

We recently switched to version 2.50 of Everest, so these scores are not comparable to previous tests with version 2.20. The memory latency test continues to show a 10% advantage for the nForce4's memory controller. The Intel D975XBX's performance explains the lower scores in our synthetic benchmarks and other benchmarks. Hopefully, Intel will be able to extract additional performance in future BIOS releases.

Overclocking Performance

The overclocking performance graphs have been added to the standard benchmark test suite and should allow for a better comparison on the overclocking capabilities of tested boards. For more details on the specific overclocking abilities of this board, please refer to the Overclocking and Memory Stress Test section in the Basic Features section.

The front side bus overclocking results are impressive for the other Intel 975x boards and still exceed those of the Asus P5N32-SLI. The Intel D975XBX board cannot compete with the other 975x based boards at this time. The BIOS options available certainly hinder this board compared to the more performance-oriented solutions from Asus and Gigabyte. We certainly feel the board is designed well and has the capability of matching the other solutions provided that the BIOS is properly tuned and the FSB options are extended.



Gaming Performance

The Intel 975X platform offers a very competitive gaming platform when compared to the NVIDIA nForce 4 Intel Edition SLI. The performance of the Intel D975XBX is at or near the top or bottom in the benchmarks. We repeated our test suites several times, but the scores remained consistent. It is obvious that the board has potential, and in the areas where we can track the minimum and maximum frame rates, the board was extremely consistent in its averages.



Disk Controller Performance

With the variety of disk drive benchmarks available, we needed a means of comparing the true performance of the wide selection of controllers. The logical choice was Anand's storage benchmark first described in Q2 2004 Desktop Hard Drive Comparison: WD Raptor vs. the World. The iPeak test was designed to measure "pure" hard disk performance, and in this case, we kept the hard drive as consistent as possible while varying the hard drive controller. The idea is to measure the performance of a hard drive controller with a consistent hard drive.

We played back Anand's raw files that recorded I/O operations when running a real world benchmark - the entire Winstone 2004 suite. Intel's iPEAK utility was then used to play back the trace file of all IO operations that took place during a single run of Business Winstone 2004 and MCC Winstone 2004. To try to isolate performance differences to the controllers that we were testing, we used the Maxtor MaXLine III 7L300S0 300GB 7200 RPM SATA drive in all tests. The drive was formatted before each test run and a composite average of 5 tests on each controller interface was tabulated in order to ensure consistency in the benchmark.

iPeak gives a mean service time in milliseconds; in other words, the average time that each drive took to fulfill each IO operation. In order to make the data more understandable, we report the scores as an average number of IO operations per second so that higher scores translate into better performance. This number is meaningless as far as hard disk performance is concerned as it is just the number of IO operations completed in a second. However, the scores are useful for comparing "pure" performance of the storage controllers in this case.

Our testing results in RAID 5, 0, and 1 with the Intel ICH7R was successful, but we did not have time to properly complete testing of the other storage controllers for this article. We will have published RAID results for all tested boards in our 975X roundup along with results from the NVIDA based P5N32-SLI.

The performance patterns hold steady across both Multimedia Content IO and Business IO, with the on-board NVIDIA nForce4 SATA 2 still providing the fastest IO, followed closely by the Intel ICH7R, Silicon Image 3132, and Marvell 88SE6141 SATA 2 controllers. The Silicon Image 3114 solution on the Intel D975XBX is a RAID only controller and resides on the PCI bus.



Firewire and USB Performance

After looking at many options for Firewire and USB testing, we finally determined that an external USB 2.0, Firewire 400, and Firewire 800 hard disk would be a sensible way to look at USB and Firewire throughput.

Our first efforts at testing with an IDE or SATA drive as the "server" yielded very inconsistent results, since Windows XP sets up cache schemes to improve performance. Finally, we decided to try a RAM disk as our "server", since memory removed almost all overhead from the serving end. We also managed to turn off disk caching on the USB and Firewire side by setting up the drives for "quick disconnect" and our results were then consistent over many test runs.

We used 1GB of fast 3-2-2-8 system memory set up as a 450MB RAM disk and 550MB of system memory. Our standard file is the SPECviewPerf install file, which is 432,533,504 bytes (412.4961MB). After copying this file to our RAM disk, we measured the time for writing from the RAM disk to our external USB 2.0, Firewire 400, or Firewire 800 drive using a Windows timing program written for AnandTech by our own Jason Clark. The copy times in seconds were then converted into Megabits per second (Mb) to provide a convenient means of comparing throughput. Higher Rates therefore mean better performance in this particular test.

Possibly the most interesting finding in our Firewire and USB throughput tests is the continued performance of an external hard drive connected to Firewire 800. Firewire 800 does make a difference and should be a standard option at this time. Our benchmarks show Firewire 800 is up to 46% faster than a drive connected to the more common Firewire 400, and about 29% faster than USB 2.0. The Intel D955XBK had the Firewire 800 option, but for reasons unknown, it was dropped on the Intel D975XBX.



Ethernet Performance

The current motherboard test suite includes LAN performance measurements. All of these boards utilize PCI Express controllers with the only difference being the supplier of the core logic.

The Windows 2000 Driver Development Kit (DDK) includes a useful LAN testing utility called NTttcp. We used the NTttcp tool to test Ethernet throughput and the CPU utilization of the various Ethernet Controllers used on the Intel 975x motherboards.

We set up one machine as the server; in this test, an Intel system with an Intel CSA Gigabit LAN connection. Intel CSA has a reputation for providing fast throughput and this seemed a reasonable choice to serve our Gigabit LAN clients.

At the server side, we used the following Command Line as suggested by the VIA whitepaper on LAN testing:

Ntttcpr -m 4,0,‹server IP› -a 4 -l 256000 -n 30000

On the client side (the motherboard under test), we used the following Command Line:

Ntttcps -m 4,0,‹client IP› -a 4 -l 256000 -n 30000

At the conclusion of the test, we captured the throughput and CPU utilization figures from the client screen.

The Intel 82573L PCI Express x1 LAN solution exhibits excellent throughput and CPU utilization rates. The Broadcom 5789KFB option on the Gigabyte board offers excellent throughput, but at a slightly higher CPU utilization compared to the other solutions. The Marvell 88E8062 PCI Express x4 LAN solution continues to offer the highest standard throughput of the tested options.

All standard Ethernet tests were performed with standard frames and the NVIDIA Active Armor suite disabled unless otherwise noted. Gigabit Ethernet supports Jumbo frames as well and provides a further reduction in CPU overhead. We added another test scenario in which ActiveArmor and Jumbo frames were enabled on the Asus P5N32-SLI Deluxe board via the 6.82 WHQL platform driver set. This is shown for illustrative purposes and shows the favorable impact of this technology.



Audio Performance

We limited audio testing to the Rightmark 3D Sound version 2.2 CPU utilization test and tested with sound enabled to show the performance effects on several games. The Rightmark 3D Sound benchmark measures the overhead or CPU utilization required by a codec or hardware audio chip.

The Sigmatel STAC9221D codec on the Intel D975XBX board does not fully support 3D Hardware, EAX1, or EAX2 modes as the other on-board codecs do at this time. Consequently, its performance is highly dependent upon the CPU and gaming support will be limited to generic OpenAL or 2D modes.

The Sigmatel STCAC9221D codec has extremely high CPU utilization rates in the 2D audio tests when utilizing 32 buffers, which is a minimum requirement in most of today's games. The BlueGears/HDA Mystique 7.1 Gold still has the highest overall utilization rates of the audio solutions tested. BlueGears has confirmed a new driver release that will offer improved performance in several areas. The Realtek R1.29 driver release has improved CPU utilization rates over previous releases. This driver set has been supplemented with the R1.30 release that will be tested shortly. The Sound Blaster X-FI has the lowest rates with the Sound Blaster Live! 24-bit solution on the Gigabyte board following closely. Let's find out how these results translate into real world numbers.

The audio performance numbers are interesting as the Sigmatel 9221D creates frame rate losses consistent with the other solutions even though the audio output is in 2D mode. This is primarily due to the design of the drivers and codec that rely heavily on the CPU to process the audio streams. Serious Sam II has an average loss of 45%, Half Life 2 at 26%, Splinter Cell at 12%, Battlefield 2 at 13%, and F.E.A.R. at 6%. The surprising number is the performance of the Sound Blaster X-FI in Serious Sam II with a 29% decrease in frame rates at this time. Serious Sam II sounded bright and tinny on the Sigmatel 9221D and did not offer an enjoyable game playing experience in Splinter Cell, HL2, BF2, or F.E.A.R. where 3D sound is a must. While the audio output quality of the Sigmatel 9221D still exceeds that of the Realtek ALC850 in games, it would not be our choice for a true gaming solution.

Obviously, if you are a serious gamer, then a dedicated sound card is still a requirement to ensure consistent frame rate averages across a wide variety of games. We noticed in our Battlefield 2, Serious Sam II, and Half Life 2 testing that the ALC882M solution would stutter in intensive scenes, creating frame rates in the low teens momentarily. We will be testing the Realtek R1.30 drivers in our next article to see if the minimal frame rates and stutter issues have been improved.

The included Intel Audio Studio software offers excellent configuration options in an impressive yet easy to use package. The Sigmatel 9221D audio solution displayed excellent sound characteristics in music, video, and DVD playback throughout our testing and should seriously be considered as the main audio component if gaming is not your priority. However, while the audio output quality in games was acceptable, the lack of basic EAX compatibility and performance degradation is not.



Final Words

The Intel D975XBX is an interesting solution for the Intel Enthusiast at this time. The performance of the board was average or below in all testing phases while stability was superb. In fact, unless we were overclocking the board past its obvious limits, we never experienced any stability issues. Unlike other boards reviewed recently, we did not find any test issues with our peripheral inventory. The Intel D975XBX exemplifies Intel's trend of offering very stable and secure board solutions with excellent documentation and support.

With that said, let's move on to our performance opinions regarding this board.

In the video area, the inclusion of two physical PCI Express x16 slots that fully supports x8 bandwidth operation for dual graphics cards is a valuable feature for the workstation user or enthusiast. The board fully supports ATI CrossFire mode in our internal testing. We are waiting on a X1900XT MasterCard to arrive for further CrossFire testing, but we did not discover any issues with the X850XT CrossFire solution and 6.1 driver set.

In the on-board audio area, this board offers the Sigmatel STAC9221D High Definition audio codec. The excellent Intel Audio Studio software suite provides Jack-Sensing, S/PDIF Out support, interrupt capability, and Dolby Master Studio support among other options. The audio output of this codec in the music, video, and DVD areas is very good to excellent. The audio quality in gaming was acceptable, but the performance was mediocre considering the lack of EAX compatibility. If you plan on utilizing this board for gaming, then our only recommendation is to purchase an appropriate sound card. Further information about the Sigmatel family of HD audio codecs can be found here.

In the storage area, the Intel board offers a wide variety of storage options with additional SATA RAID ports. The board fully offers Intel's excellent Matrix RAID system and offers Hot Swap, NCQ, and 3Gb/s capability. Intel supplements their native SATA capability with the Silicon Image SiI 3114 SATA chipset featuring support for Hot Swap and 1.5Gb/s operation. The SiI 3114 resides on the PCI bus and Intel's implementation is for RAID 0, 1, and 0+1 operation only. The board offers the standard eight Intel USB ports and two IEEE 1394a ports utilizing the TI TSB43AB23 chipset. However, we believe that Firewire 800 should have been offered on this board, since it was included on the D955XBK.

In the performance area, the Intel D975XBX generated scores that were lower than the other boards in most benchmarks. The overall performance of the board was disappointing at times, but was within range of the other 975x offerings. The stability of the board was superb during testing and the results in certain game benchmarks offer hope for improvement in the future. We will review the performance of this board again when our retail version arrives and then update our findings.

The Intel D975XBX is a board designed and marketed for the Intel Enthusiast, yet it excels at being a full-featured home office or occasional workstation solution. Intel had a golden opportunity to take a very solid design and improve upon it for their targeted enthusiast market. Our expectations of the board were set by the design and performance of the Intel D955XBK.

Intel took a few steps forward with the board and yet at the same time, it took a few steps back. Intel did rectify the D955XBK cooling issues around the MOFSETS and increased the stability of the board with the 5-phase power regulation system. The inclusion of true x8 operability for the primary and secondary PCI Express connectors along with full ATI CrossFire support addressed the lack of performance for multiple GPU solutions. The improved BIOS options and increased voltages are a step in the right direction and shows that Intel is trying to match other suppliers in their ability to increase performance.

However, we feel that Intel made the following errors in the design and execution of a board targeted to the "advanced gamer and power-user". The entire process of setting up the BIOS in the advanced section for overclocking should be simplified. If Intel is serious about targeting the enthusiast user, then the question and answer section in the BIOS needs to be dropped. The process for overclocking the system via FSB adjustments needs to change from a fixed percentage rate to the ability to enter a FSB value. The voltage, memory frequencies, and bus options need to be further expanded. The BIOS needs to be able to self-recover when the board is unable to boot at extended settings. The current shutdown/jumper/startup process ensures frustration on the user's behalf. The bottom line is: if you are going to allow overclocking, then make it as user-friendly as possible.

The inclusion of the SiI 3114 RAID chipset is an error when the excellent SiI 3132 is available at this time. The SiI 3132 is a PCI Express device unlike the SiI 3114 and offers NCQ, Port Multiplier, and 3Gb/s support. The removal of FireWire 800 support that was offered on the D955XBK board is also an error.

We certainly look forward to Intel's next enthusiast board as they definitely are on the right path. Our expectations were quite high for this board, but it has left us with heartache, as it could have been much more.