Intel 900 Series Processors and Chipsets

With the introduction of the new "Presler" based based 900 series CPU's, Intel has taken the first real steps towards the transition to their next generation of processor microarchitecture. While the upcoming "Conroe" processors will be revolutionary in technology and design, this doesn't take anything away from the now available 900 series of processors that Intel has just recently introduced.

The 900 series of processors, including the power-house Pentium Processor Extreme Edition 955, sees Intel implementing it's last real set of changes before fully transitioning away from their Netburst architecture. Once thought to be the base that would take Intel into the 9GHz speed range, the Netburst architecture is simply starting to show it's age. The previously satisfactory practice of one upping the competition with speed increases alone has well been overcome with showcasing new operational features and rapidly advancing technology. By infusing the newer technologies into the older platform, the 900 series processors are a worthy successor to the previous models and a great way to end the current processor line on a high note.

Intel Pentium D 920 - 950

Starting with the more mainstream desktop processors, the 920 through 950 models, we see much more than merely a die-shrunk version of their previous 800 series ("Smithfield") counterparts. After shrinking the die in order to improve performance and reduce power consumption levels Intel moved on to double the cache from 2MB to 4MB. The design of the new Pentium D processor has been changed so that it utilizes two individual "Cedar Mill" cores on one Presler chip giving each core it's own 2MB of L2 cache as opposed to the 2MB that was available with Smithfield, but had to be divided equally among the 2 halves of the core. "Cedar Mill" refers to the 6X1 Series of chips which are the single core relative of the Pentium D. They share most features including the 65nm core, EM64T support, Execute Disable Bit, and later in the year will be acquiring the EIST right along with the Pentium D 950 Processor.

Pentium 4 Processor Supporting Hyper-Threading Technology Specification Chart

By shrinking the processor die from 90nm to 65nm, Intel has opened the door to adding more transistors, while at the same time lowering power, and reducing heat being released. This reduction in die size, while sticking with the same 300mm wafer fab process has allowed Intel to save money both in migratory production costs and also in higher yields than the original Smithfield based Pentium D. The "Smithfield" based Pentium D used a pair of "Prescott" cores which had been physically fused together to work as one. This solution turned out to be problematic because, during manufacturing, if one core was determined to be bad, then second core had to be discarded and could not be re-used. The new process insures that there will be a much higher success rate with the cores and Intel could potentially reduce prices if needed to better compete in the market. As it stands now, the 900 series of processors are priced right in line with their 800 series counterparts so anyone with a compatible motherboard will not be forced to pay a premium to step up to the latest and greatest processor.

Presler chip with dual "Cedar Mill" cores

As with the 800 series of Pentium D processors, the 900 series units also require a motherboard with the 945G or higher chipset since that is where the support for dual core (or dual chip in this case) processors began. As always, it's best to check with your motherboard vendor of choice in order to insure compatibility with the model motherboard that you are looking at purchasing. BIOS updates are often required to update microcode on the boards to properly identify and support new CPU speeds and features.

Pentium D and Pentium Processor Extreme Edition Specification Chart

Intel Pentium Processor Extreme Edition 955

In addition to all of the features available in the Pentium D 920 - 950 processors, the Pentium Processor Extreme Edition 955 chips also have the added bonus of the Hyper-Threading technology being left intact allowing the processing of 4 threads at a time. Through it's 4 processors (2 physical, 2 virtual), the Pentium Processor Extreme Edition is a formidable force against anything available on the market today. Along with the speed bump that you get over the standard version of the Pentium D 950, the Intel Pentium processor Extreme Edition has a 1066MHz front side bus and an unlocked bus ratio (overspeed protection) that allows experienced enthusiasts to work with the processor for added technical flexibility to enhance their experience to the maximum limits of performance. Intel decided to disable SpeedStep (EIST) on the 955 to prevent core throttling, but still employs it's own TM1 (Thermal Monitor 1) mechanism to protect against overheating.

Quick Review: Hyper-Threading vs. Dual Core (from Intel's Dual-Core flash demo)

• A single threaded processor (no Hyper-Threading) is only able to process one software thread, or single instruction sequence, at a time in a serial manner.
• An Intel processor with Hyper-Threading Technology can execute two software threads in an increasingly parallel manner, utilizing previously unused resources.
• Intel has introduced a number of dual-core processor-based platforms that embed two execution cores into a single processor.
• An Intel dual-core processor enables each thread to be processed in it's own execution core for truly parallel execution. An Intel dual-core processor with Hyper-Threading Technology enables execution on four threads in parallel.

Intel 975X Express Chipset

Intel has very conveniently released the new 975X Express chipset alongside the new 900 series of processors. While both the Intel 955X and 975X Express Chipsets support the Pentium Extreme Edition 955 CPU, as always you'll get the greatest support on the latest platforms. Featuring support for both the 1066MHz and 800MHz System Bus, the 975X Express chipset will support processors ranging from the Pentium 4 Processor, all the way up to the Pentium Processor Extreme Edition.

Dual PCI Express controllers enable ATI CrossFire support and allow either 1 PCI Express x16 card to run at full bore, or dual PCI Express cards to split the lanes and provide both with PCI Express x8 performance. Intel High Definition Audio provides premium digital sound which reigns far superior to most all of the other audio chips which are integrated into desktop motherboards today. Intel Matrix Storage Technology helps to both protect your data and provide the ability to stripe your SATA 3G hard drives in order to enhance performance. Although mainly known for their superior business platform motherboards, Intel has developed a chipset and subsequent motherboard which provides their world renown stability with an incredibly potent desktop entertainment platform.

Motherboard makers across the board have embraced the 975X Express chipset and are rushing forth motherboards showcasing their greatest features and latest technology to show off this top of the line Intel CPU. Some samples are shown below along with their ASI SKU numbers for your easy ordering pleasure.

Intel D975XBXLKR "Bad-Axe" ASI SKU 43458	ASUS P5WD2-E Premium ASI SKU 44647	Gigabyte GA-G1975X ASI SKU 43666
Features VIIV Technology Enabled ATI CrossFire PCI Express x16 PCI Express x8 Intel High Definition Audio SATA 3G (RAID 0, 1, 5, 10) GbE Ethernet	Features ATI CrossFire Dual Channel DDR2 PCI Express x16 PCI Express x8 SATA 3G (RAID 0, 1, 5, 10) Intel MPT PEG Link AI NOS	Features ATI CrossFire Dual Channel DDR2 PCI Express x16 PCI Express x8 GbE Ethernet Creative Sound Blaster Live SATA 3G (RAID 0, 1, 5, 10) Gigabyte Turbojet Technology

Pentium D 900 vs. Pentium D 800 Comparison Chart

Final Thoughts...

What the above table doesn't really showcase is the vast improvement over the 800 series of Pentium D processors. Performance wise, the L2 cache increase helps on most benchmark tests. Thermal tests show that Intel has gone a long way towards reducing the power consumption which haunted the previous models. The shift in architecture to a true dual-core versus a rushed out effort to keep the competition from running away with all the good marketing material makes for a very good processor this time around.

As Intel prepares for the upcoming "Conroe" line, they added features like VT to the 900 series (although no one really seems to know how to take advantage of the technology at this time). With the addition of the new Pentium Processor Extreme Edition 955 chip, Intel has brought forth a powerhouse CPU for gaming enthusiasts and even left open tweaking options for the more adventurous among them. The last hoorah of the Netburst series looks to be a legitimately strong performer for us to look back on after Intel transitions to a new platform in the coming year.