It has been some time here at the TweakTown labs since anything new from Intel crossed our paths. In the past, Intel's fast and furious rush to the highest GHz CPU has led us with quite a few processors cores on our test bed but now with the move on performance per watt, Intel has slowed down the rush of faster CPU's and focused more in what can be done to improve the current batch of Pentium 4 systems.
Dual Core is now the main stage for both Intel and AMD in the fight for PC performance. Core speeds have hit the wall in terms of gaining more relative performance, higher clocks simply don't offer as much to the end user. Adding two cores into a single package gives the ability to have a Symmetric Multi Processor setup without having to buy two separate CPU's.
Today we will be taking a look at the two latest Intel cores to hit the market in terms of Dual Core support: the already available Smithfield and the newest member to hit the market, the Presler. So come with us as we take a look at the Intel Pentium D 840, Intel Pentium Extreme Edition 840 and the Intel Pentium Extreme Edition 955 and see what each has to offer, along with Intel's latest motherboard based on the 975X chipset.
Dual Core in Detail
Dual Core started some six months ago with Intel introducing the first desktop Dual Core CPU, and AMD going the opposite road with the first Dual Core server CPU. Dual Core is simple on the Intel front; it's just the art of using two separate CPU dies and placing them into a single physical package.
The Intel parcel has the CPU dies due off from each other, meaning they do not physically connect like the AMD Athlon 64 X2, which has two dies built into one direct package. Intel's Dual Core in technical specs resembles a Dual Xeon system. There are two separate CPU's using the Front Side Bus in order to communicate, which tends to be the Intel bottleneck compared to AMD.
AMD's Dual Core uses a Hyper Transport link to connect the two CPU's together to communicate without having to go to the main bus or memory controller, which allows core to core communication for parallel synchronisation. Intel's Dual Core needs to go back to the Northbridge and send a request to the second core if the first core wishes to know what core #2 is doing - an extremely latency heavy process. None the less, two cores work better than one and Intel has its design on the table.
Currently, Intel has two versions of the Smithfield core, the Pentium D 800 series and the Pentium Extreme Edition 800 series. First let's look at the Pentium D incarnation.
Pentium D is the mainstream CPU for Intel, Pentium D is set to replace the entire Pentium 4 range. The major points for the Pentium D are its 800MHz FSB, support for EM64T, 1MB L2 cache per core (2MB total cache), SSE3 and Enhanced SpeedStep Technology. The Pentium D uses Intel's Strained Silicon at 90nm, which requires quite a bit of power to run compared to Silicon on Insulator like AMD uses. Pentium D's overall characteristics put it similar speeds clock for clock with the Pentium 4 600 series. The major advantage the Pentium D has is rather than a logical second processor, it has a physical CPU, so it doesn't have to wait for the first core to complete its task for the second core to operate. As well as this, there is a separate L2 cache for the second core, allowing it to have its own addressing while the first core is in operation, where Hyper Threading doesn't. Pentium D also features SpeedStep to place the CPU into the same reduced core states that the Pentium 4 600 series features.
The Pentium Extreme Edition 800 series uses the exact design as the Pentium D only a few extra tricks have been added to make it more attractive to the enthusiasts. Firstly SpeedStep is disabled, so no core throttling, however, the TM1 is still used for overheat protection. Second is the inclusion of Hyper Threading on each core. The Pentium Extreme Edition resembles under Windows Environments a Xeon Prescott server with two CPU's with Hyper Threading on each CPU, leaving Windows finding four separate cores. Lastly, and most importantly, the Intel Pentium Extreme Edition CPU is multiplier unlocked, that's right, overclockers will love to get their hands on these. Intel leaves the multipliers from 14x up to 60x unlocked for your overclocking pleasure similar to how AMD leaves the Athlon 64 FX opened for raising the multiplier above the factory set ratio.
Presler is the last of the line for the Intel Netburst Architecture. Presler is the first to use the latest 65nm strained silicon technology. Presler core CPU's aren't technically a Dual Core but more a Twin Core system.
Smithfield cores when produced were made together in a single package, which caused some serious issues in usable yields. If one of the cores failed testing, both units had to be scrapped. Presler cores are actually separate dies on a single package linked together.
The cores are physically about 5mm away from each other. This gives Intel a much higher yield rate. The cores are tested separately, if both cores communicate together, they are glued onto the Dual Core package and sold as a either a Pentium D 900 series CPU or the Pentium Extreme Edition 900 series CPU.
One of the major architecture changes is Intel's Virtualisation technology, formally known as the Vanderpool technology. Vanderpool allows the CPU to split off and run multiple Operating Systems at the same time on one system.
The last of the enhancements to the Presler core is an increase in the Level 2 cache. Smithfield used the same L2 cache size as the Pentium 4 500 series of 1MB per core. Presler uses the same size cache per core as the Prescott-2 M core, that's 2MB per core, in all a total of the 4MB on the Presler cores. Presler will be available in both Pentium D series of two cores without Hyper Threading and the Extreme Edition with two cores and Hyper Threading.
The New Motherboard
Intel's latest platform launches - The Motherboard
Intel's latest processor is a LGA775 series CPU only, you won't find them in Socket 478 - in fact you won't find socket 478 CPU's being made available for the retail market at all. The design of the CPU is almost identical to that of the previous generations of LGA775 CPU's, but it's under the surface that things change.
Under the heatspreader we see the way Intel has laid out the Presler Dual Core. Presler uses two separate cores spaced apart from each other and this is done for two reasons: 1) heat dissipation; moving the two cores away from each other allows for a even heat dissipation across the surface of the die. 2) Smithfield based processors were hard to get in high yields due to the way the die was made. Both cores were put into a single package. This meant that if one of the two cores were faulty, both had to be scrapped. In the Presler design, if one of the cores were faulty, it can be removed from the package and used as a single core CPU setup and a fresh core can be added to the package.
Now we get a first hand look at the motherboard Intel has manufactured to take advantage of the new processors. This board is not only a reference design, but also the very same board Intel will sell in its Desktop board range, under the name of D975KBX.
First we take a look at the general layout and placement of the primary connectors. For a board from Intel, it is laid out similar to a high-end motherboard. The 24 pin ATX connector along with the IDE and FDD connectors are on the right hand side of the board behind the colour coded DDR-2 memory slots. Intel also inverts the IDE connecter 90 degree pushing the cable on the horizontal giving the flat ribbon cable a better air flow profile. The 8 pin CPU voltage power plug is located at the top left of the board behind the I/O panel near the PS/2 ports. Intel has also put in a 4 pin Molex power connector behind the I/O panel as well mid way down. These are used when working with multiple graphics cards to give the PCI Express slots more power.
Now we come to the slots. You many have noticed three PCI Express x16 slots. This is Intel's top of the line board and Intel has moved in to take advantage of multiple graphics technology. The top most PCI Express x16 slot is a true electrically x16 slot, however, when going into Multiple Graphics mode, the slot reverts to an x8 slot. The second PCI Express x16 slot is electrically x8 only, this is used when a second graphics card is installed. The final PCI-E x16 slot works at only the x4 rate. This is if you want to add in a third graphics card to use up to 6 monitors. Also you can use server PCI-E x4 RAID controllers in this slot. There is simply no limit when it comes to PCI Express.
To add legacy support, there are two PCI slots, one at the very bottom of the board and one between PCI Express x16 slot 2 and 3.
Intel's power management for the D975KBX is FMB2.1. This new specifications are introduced for the 65nm Presler and Cider Mill cores. The new specifications calls for no less than 4-5 phase voltage regulation system to deliver a stable voltage to the new Presler cores which run at 1.3v with up to 130 watts needed for stability. While not a requirement, Intel has passively cooled the Mosfets with heatsinks, another score for Intel in the cooling department.
The I/O plane gives you all of the connectors you will need - two PS2/, one serial, one parallel, one SPDIF output, four USB, one Firewire-400, one Gigabit RJ-45, 5 Stereo Audio and one Toslink-in.
The New Chipset
Intel's latest platform launches - The Chipset
Now we get to what controls the board, the new Intel 975X chipset. The chip is a two part series, like all of the chipsets from Intel. It's very unlikely we will see single chip unless a Northbridge is integrated into the Intel CPU in the future.
The block diagram shows Intel's layout of what and how the 975X supports and how it is connected. The Dual PCI-E X16 slots are routed off the Northbridge to either a single x16 slot or two x8 slots. The DDR-2 memory controller is also located on the Northbridge and has been tweaked to work with the latest DDR2-800 memory (though there is no official support for this yet). One of the major triumphs of the 975X Northbridge is that Intel has worked with ATI to achieve official support for Crossfire Dual Graphics. That's right, if you plan to go ATI Crossfire; 975X supports this and it is incorporated into the latest Catalyst drivers on the web. Intel hasn't been granted SLI certification yet and we aren't sure if this will happen, as nVidia already makes its own Intel Pentium 4 chipsets for SLI, but these have been problematic with supporting the Pentium XE chips in the past.
The Southbridge is the same ICH7R used on the 955 and 945 series chipsets. This includes two SATA-II controllers supporting four SATA 2.5 ports, Azalia High Definition Audio, 6 PCI Express lanes, one IDE controller, 6 PCI Masters and 8 Hi Speed USB 2.0 ports. The link connecting the chips is Intel's Direct Media Interconnect operating at 2GB/s.
The Intel board uses two passively cooled heatsinks to disperse the heat from the chipset. One rather large one on the Northbridge and a smaller low profile one on the Southbridge.
Intel has now started to jazz up even their desktop boards with additional features. Since the ICH7 series only has a single IDE controller and the four SATA ports on the Southbridge can be used up pretty quick, Intel has added a Silicon Image SIL3114 PCI SATA controller chip. This chip uses the older SATA-150, so despite the SATA-II ports at the bottom of the board that are connected to the chip, you will only get SATA-150 speeds out of it. Another limitation of the chip is it uses the PCI bus to connect, which when using RAID can eat up all or just about all of the PCI bandwidth.
Firewire is now a household name with a lot of products using the standard, like Apple Ipod, DV cameras and external HDD storage boxes. To that end a Texas Instruments PCI based IEEE-1394 chip is added to give two Firewire-400 ports. One is located on the back I/O, the other needs to be connected to a header bracket or to a front panel case Firewire port.
Lastly we come to Intel's latest Gigabit Ethernet controller, the Tacoma. This new chip is a 10/100/1000 Gigabit Ethernet PCI-Express x1 based chip. This chip is also a part of gaining Intel ViiV certification, which we will cover when our ViiV system arrives at our labs.
Now this is something that will take quite a few people by surprise. Intel is now adding overclocking features to its boards - and not just little tweaks - there is quite a bit of grunt under the hood.
Intel hasn't jumped on the automatic overclocking bandwagon like ASUS, MSI and Gigabyte but they have included a few tweaks. To access the overclocking features you need to enter the BIOS, go to the advanced top menu and select the Chipset Configuration sub menu. Once there you will see the Default Setting Override option. Once in there you are faced with the Intel overclocking setup. Intel has a lot of writing up in this screen warning you that altering the frequencies and voltages will void your CPU and motherboard warranties as well as possibly affect system stability. You need to say you accept this and the overclocking options are then selectable.
When running a Pentium Extreme Edition CPU your first option is Processor Ratio Multiplier. You can adjust this from the default minimum of 13x up to a maximum of 60x.
Next option on the list is the Processor CPU VID. This allows you to change the processor voltage from 1.3v (default for Presler or 1.38v for Smithfield) up to a maximum of 1.6v in 0.025v increments.
Next we have the Host Frequency Override which allows you to select different FSB settings. Intel does limit the amount of FSB you can choose unfortunately; there are four options only: 533, 800, 1066 and 1333MHz. You then are given the option to boost the PCI, PCI-E frequencies - leaving them at default locks them to 100MHz for PCI-E and 33MHz for PCI.
The last two voltages in this setting are MCH voltage override and Front Side Bus voltage override. This allows you to stabilise the FSB and the MCH to ICH links when overclocking. Ranges for both are 1.2v up to 1.4v in 0.1v increments.
To overclock the DDR2 you need to exit this menu and locate the Memory Configuration sub menu in the advanced top menu. Here you can adjust the DDR-2 memory speed to 333MHz, 400MHz, 533MHz, 667MHz or 800MHz. DDR2 voltage control is also located here with settings from 1.8v up to 2.2v.
With these options we did a two stage overclock of the CPU. First we lowered the multiplier back to 13x and raised the FSB to 1333MHz to see if the board would post. It did, but refused to run Windows at this speed, no matter how much voltage tweaking we did.
Next we did a multiplier overclock to see how far the CPU would go. We raised the multiplier from its default of 13x (266MHz x 13 = 3458MHz) and went up each multiplier till we hit a wall. In air we managed to get to 15x, which gave us 3.9GHz. We then stuck our Gigabyte 3D water cooler onto the unit to see what we would get. With this we got to 16x which gave us a very impressive clock speed of 4.2GHz - which is about a 800MHz overclock past the default speed, on a reference motherboard! We did encounter a few stability problems relating to our test PSU; however, given the right conditions, this CPU manages to pull some serious clocks and should go a long way to making Intel's latest CPU and the 975X chipset a true gamers option, especially given official ATI Crossfire support.
Benchmarks - Test System Setup and SiSoft Sandra
Test System Setup
Memory: 2x 512MB Corsair DDR2-800
Hard Disk: 2x Seagate 7200.9 in RAID 0 (Supplied by Seagate)
Motherboard: Intel D975KBX
Graphics Card: ATI Radeon X800XT Platinum (Supplied by ASUS)
Operating System: Microsoft Windows XP SP2
With these tests we put four CPU's to the test and two separate platforms.
In the CPU department we compared the 3.4GHz Pentium 4 600 series CPU, 3.4GHz Pentium D, 3.4GHz Pentium Extreme Edition 800 series and the new Pentium Extreme Edition 955 with the Intel 975X motherboard.
To compare the I955 chipset vs. the I975 chipset, we put the Pentium Extreme Edition 800 series CPU into both boards and ran the tests. This is the reason you will see two sets of XE800 results in our testings.
Version and / or Patch Used: 2005 SR3a
Developer Homepage: http://www.sisoftware.co.uk
Product Homepage: http://sisoftware.jaggedonline.com/index.php?location=home&a=TTA&lang=en
Buy It Here
SiSoft Sandra (System ANalyser, Diagnostic and Reporting Assistant) is a synthetic Windows benchmark that features different tests used to evaluate different PC subsystems.
Here we can see that the I975 vs. I955 in terms of memory that the new chipset has done a good job tweaking the memory controller. In respects of the rest, the Pentium XE 955 with the faster FSB has the extra advantage to crunch more numbers.
Benchmarks - Super PI
Version and / or Patch Used: 1.1e
Developer Homepage: http://pw1.netcom.com/~hjsmith/Pi/Super_Pi.html
Product Homepage: http://pw1.netcom.com/~hjsmith/Pi/Super_Pi.html
Developed by some folks from the University of Tokyo (yes, Japan), Super PI is a small utility that does just as the name implies. It figures PI to a set number of decimal places. Since PI is an infinite number to the right of the decimal point, the utility measures the time it takes to figure a set number of places. It runs the calculations a set number of times and gives a time for the completion of the task. This is a simple and effective way to measure the raw number crunching power of the processor being used to compile the results.
Super PI cuts the time taken to calculate PI to 32million decimal places down quite a bit.
Benchmarks - Media Encoding
For this test we used Cyberlink Power Producer in conjunction with DIVX 6.0Pro to encode "The Matrix" MPEG2 down to a MPEG-4 High resolution video file.
The Cyberlink software comes with its own time clock to indicate the time taken to encode the movie as well as average CPU usage and average FPS during the encode. We used DIVX 6.0 due to its support for Dual Core CPUs as well as Intel SSE3 and Hyper Threading.
The results seen here are pretty clear and just what we expected.
Benchmarks - PCMark
Version and / or Patch Used: 2005 Build 1.3.0
Developer Homepage: http://www.futuremark.com
Product Homepage: http://www.futuremark.com/products/pcmark04/
Buy It Here
PCMark is a multipurpose benchmark, suited for benchmarking all kinds of PCs, from laptops to workstations, as well as across multiple Windows operating systems. This easy-to-use benchmark makes professional strength benchmarking software available even to novice users. PCMark consists of a series of tests that represent common tasks in home and office programs. PCMark also covers many additional areas outside the scope of other MadOnion.com benchmarks.
PCMark05 also has support for multiple cores and to this degree shows the 955XE winning out quite comfortably.
Benchmarks - 3DMark05
Version and / or Patch Used: Build 120
Developer Homepage: http://www.futuremark.com
Product Homepage: http://www.futuremark.com/products/3dmark05/
Buy It Here
3DMark05 is the latest version in the popular 3DMark "Gamers Benchmark" series. It includes a complete set of DX9 benchmarks which tests Shader Model 2.0 and higher.
For more information on the 3DMark05 benchmark, we recommend you read our preview here.
3DMark05 also has support for dual core; we can see the Pentium XE 955 manages a slight lead over its older counterpart.
Benchmarks - F.E.A.R.
Version and / or Patch Used: Unpatched
Timedemo or Level Used: Custom Timedemo
Developer Homepage: http://www.vugames.com
Product Homepage: http://www.whatisfear.com/us/
Buy It Here
F.E.A.R. (First Encounter Assault Recon) is an intense combat experience with rich atmosphere and a deeply intense paranormal storyline presented entirely in first person. Be the hero in your own spine-tingling epic of action, tension, and terror...and discover the true meaning of F.E.A.R.
Again, F.E.A.R. supports Dual Core CPU's. Here the Pentium XE 955 is just about equal to the XE 840, though both manage to beat out the Pentium D 840 and the Pentium 4 660.
Benchmarks - Doom 3
Version and / or Patch Used: 1.3
Timedemo or Level Used: Custom Timedemo
Developer Homepage: http://www.idsoftware.com
Product Homepage: http://www.doom3.com
Buy It Here
Doom 3 is the latest game to hit our test lab and is one of the most intensive games to dates. With our own custom time demo we are able to give a realistic rating on what kind of FPS you will be achieving.
For more information on benchmarking Doom 3 we recommend you check out our extensive article regarding it here.
Here we can see the power of the new Pentium XE 955 and a slight performance increase with the new chipset over the older 955X.
It has been a long road for Netburst technology, and it has been one with highs and lows. Introduction of the first Pentium 4 on the Willamette core was plagued with heat and performance issues. Northwood's introduction was the first Pentium 4 core to actually gain a name for cool operating temperature, high speeds and introduction of SMP in Hyper Threaded CPU's. Since the death of the Northwood core, Intel has had nothing but troubles. Prescott introduced Intel to the world of voltage leakage and higher operating temps and clock limitations.
Dual Core was the only way Intel could salvage the Netburst system, and it has done a reasonably good job in order to put the Pentium D and Pentium Extreme Edition CPU's on the map. While having two high speed clocks on one small package, Intel really needs to abandon the FSB connection between the two CPUs for core to core communication, as AMD has already shown that there is another much better way to do things.
The latest instalment to Intel's Dual Core had certainly gained a few extra FPS in gaming, but its real strength is its pure number crunching and encoding abilities, feeding those long pipelines with straight forward numbers without stalls does give the Netburst architecture a one up.
The Intel 975X chipset is simply an upgrade to the I955 with the ability to run the new Extreme Edition CPU's along with the current Pentium 4 and Pentium D lines. Now all we need is more ATI Crossfire cards to keep the multiple graphics technology alive, and also hope Intel gets nVidia SLI approval but we might be waiting sometime for that to happen.