What is PCI Express?

One of the most significant changes to come to PC systems in a decade, PCI Express is a new interconnect technology designed to provide universal connectivity for use as a chip-to-chip and chip to adapter card interconnect. PCI Express architecture provides for extremely high bandwidth at low cost.

PCI Express can offer up to 70 times the bandwidth of today's PCI architecture and is scaleable for the future. PCI Express will be featured across all Intel platforms including desktop, server, workstation and in the latter half of 2004 with mobile platforms as well.  PCI Express will be the I/O architecture for everything from graphics adapters to Ethernet cards to TV tuners. This massive bandwidth will alleviate many current and future performance bottlenecks on the adapter bus.

PCI Express is based on a type of serial communications technology somewhat like that in USB or SATA hard drives.  The mechanical (physical) board connectors come in one of four types: x1, x2, x4, and x16 (see illustration to the right) in order to meet different peak bandwidth requirements.

PCI Express Technical Specs:

• Full duplex point-to-point topology
• Differential low voltage interconnect
• Embedded clocking
• Scalable frequency: Initial Bit Rate: 2.5Gb sec/lane/direction
• Scalable bandwidth - data layer is scalable to 1x, 2x, 4x, 8x, 12x, 16x, 32x lane widths
• Each PCI Express "lane" uses 4 wires - one differential pair for transmit and one pair for receive
• Enhanced Configuration and Power Management
• RAS: CRC Data integrity, hot-plug, advanced error logging/reporting
• QoS and Isochronous support
• Advanced Switching extensions

* Note: PCI Express is NOT the same as PCI-X slots, it is a totally new technology.

Key Advantages of PCI Express

PCI express is a highly flexible, reliable, modular and scalable design that will eventually replace all PCI slots on the motherboard and AGP slots.  It has better power management, native hot-plug support, backwards compatibility with PCI software, support for streaming media (such as video camera or TV), and truly scalable configurations. In addition:

• Compatible with existing PCI drivers and software and operating systems
• High bandwidth per pin. Low overhead. Low latency
• Ability to scale speeds by forming multiple lanes
• A point-to-point connection, allows each device to have a dedicated connection without sharing bandwidth
• Ability to comprehend different data structures
• Low power consumption and power management features
• Hot swap-ability and hot plug-ability for devices
• Supported by nearly 500 system hardware vendor

The x1 PCI Express slots will easily replace the standard 32-bit PCI slots and have four times the bandwidth.

The high-performance x16 configuration will have up to 4GB/sec bandwidth (8GB/sec concurrent) to replace AGP technology and will also have four times the bandwidth of AGP 8x!

With the advent of PCI Express video cards whole new worlds of 3D gaming and superior graphics performance will be possible.  ATI has already developed RADEON video cards using PCI express architecture and in just a short couple of years PCI Express will be the dominant video card interface supplied by most manufacturers and the only choice for 3D graphics power users. ATI’s video processors have a native, or “true” PCI Express interface. They can communicate directly with the PCI Express bus at PCI Express speeds (do not need to use a bridge).

DDR-II (or DDR2) memory is the new high-performance RAM architecture deigned to overcome the challenges of current DDR DRAM technology. It is the next- generation solution of main memory offering greater bandwidth and density in a smaller package at reduced power consumption and is supported by dozens of major computer vendors.

DDR2 memory chips are already being used on high-end graphic cards but this is a different standard than the one we that will be used on memory modules.  DDR2 memory modules will be similar in design but will NOT be backwards compatible with DDR memory slots*.  They will also continue to support important DDR features such as dual-channel memory support.

Normal DDR limitations at higher frequencies:

• Signal integrity
• Power Consumption

DDR2 Addresses these challenges by:

• Operating voltage is reduced from 2.5V to 1.8V
• Reduced core operating frequency
• Core frequency = 1/2 the I/O frequency 

Special New Features:

• 4-bit pre-fetch
• On-die termination
• Off-chip driver calibration

*In addition to the electrical and signaling changes DDR2 modules will have a slightly different physical interconnect than DDR modules.  The edge-connector "notch" will be in a lightly different position to prevent accidentally plugging in the incorrect module type.

LGA775

With the introduction of Intel's® Grantsdale and Alderwood Chipsets in Q2 of this year, users will get to see the next in a long line of CPU sockets to come from Intel®, the "Socket T" or LGA (Land Grid Array) 775. Intel's® launch of the CPU will most likely be with fairly limited quantities at first, but by the end of the year they are expected to be about 40% of the total shipments and top to bottom coverage of their entire desktop processor line. The introduction of the LGA775 also signals a rapid shift from the 130nm Northwood to the 90nm Prescott core. Starting with the 3.6GHz. units, all Intel processors will be built on the Socket T platform.

The new socket features an increase to 775 pins, up from the previously well known socket 478. The big change here comes in the form of where the pins are located... on the socket. The new CPU features conductor pads on the bottom where you would normally find the pins. When installed, the CPU rests on the angled pins and is pressed down onto the pins to solidify the connection. One drawback to this arrangement is that the pins are flexible, and therefore very easy to be pushed into the wrong direction. There is also 775 different pins, so if you happen to accidentally bend one of them, you're probably going to bend several of them and the chances of you getting them all straightened up to usable condition again are very slim.

Intel® will be selling 4 flavors of LGA-775 Prescott CPUs throughout 2004. The different CPUs will be; the newer P4 CPU's with an 800MHz. FSB with a FMB standard of 1.5, the same P4 800MHz CPU with a FMB of 1.0, the P4 533MHz. CPU without Hyper-Threading, and the Celeron CPU. About 17% of all Celerons shipped in 2004 are expected to be using the Prescott core. The LGA775 Prescott Celeron CPU will most likely only be aimed at Intel's own Grantsdale-GV platform motherboards.

The new LGA-775 CPUs are expected to be every bit as power-hungry as their 478-pin Prescott predecessors. The wattage drain on the new CPU's is expected to be around 100W and the heat that this will put out is causing designers to go back to the drawing boards to come up with creative ways to keep the new CPU cool. Intel has been focusing on a rounded heat sink design with semicircular bi-furcated fins. Bi-furcated fins are split about half way down their shaft. This gives the heat twice as much surface area to dissipate from without adding additional "keep-out" space to the motherboard layout. Large manufacturers such as Thermaltake have already introduced prototype units to the market for evaluation and will be completely ready by the time that the new socket motherboard hit the shelves.

Images

Although there is not very much information available on the LGA-775 CPU's at this time, we do have some images collected from around the web that we can share with you.

LGA-775 Socket T Open	LGA-775 Socket T Closed	LGA-775 Socket T CPU Bottom
LGA-775 Socket T Open	LGA-775 Socket T Closed	LGA-775 Socket T Heatsink	LGA-775 Socket T Assembly

Intel's® chipset future looks brighter than ever

With the introduction of both the Alderwood and Grantsdale chipsets expected in Q2 of this year, Intel® seems to be fulfilling it's promises of increased performance and stunning new technology. Continuing it's tradition of releasing high-end, mainstream, and cost-sensitive chipsets, they will be releasing the Alderwood chipset to meet the demands of the high-end market, the Grantsdale-P and G are aimed at the mainstream market and the Grantsdale GV and GL are taking care of the cost-sensitive market.

Alderwood (Northbridge)

Intel's® Alderwood chipset comes as the successor of the i875P Canterwood Chipset. The i875 chipset was wildly popular due to it's support of all the latest technologies, 800MHz. FSB, Hyper-Threading, Dual-Channel memory support, and PAT, (Performance Acceleration Technology), which boosted the performance level above anything attainable by the i865PE chipset. 

The Alderwood (i925x) chipset is here to continue the tradition of Intel "one-upping" themselves. Like the i875 chipset, the new i925x chipset supports 800MHz. FSB, however it does it in a new format. The Alderwood is using a LGA-775 socket to do so. LGA-775 (Land Grid Array) is the latest technology which is being introduced along with the Grantsdale and Alderwood chipsets and will be on all upcoming Prescott motherboards. The innovations continue as Intel has chosen to utilize Dual Channel ECC DDR-II on this motherboard. This effectively doubles the bandwidth of the memory on the system and will eliminate bottlenecks that are normally seen on current DDR motherboards.

• LGA-775 "Socket T"
• 800MHz. FSB
• Hyper-Threading
• PAT (Performance Acceleration Technology)
• ECC DDR-II
• PCI Express x16

Grantsdale-P and G (Northbridge)

Intel® is far from neglecting the mainstream market with it's soon to be introduced chipsets. The Grantsdale-P (i915P) and the Grantsdale-G (i915G) chipsets differ only slightly as the G has integrated graphics, and the P does not, but besides that they are basically identical. Both chipsets support the 800MHz. FSB with Hyper-Threading while utilizing the LGA-775 socket type. Dual DDR-II is also supported with the new chipset, although it is standard DDR-II and not ECC capable. The Grantsdale-P has PCI-Express x16 support for the latest and greatest graphics cards such as the ATI R400 and the NVIDIA NV40, while the Grantsdale-G will allow for PCI Express x16 and also uses integrated Intel Extreme Graphics 3. The combination on the Grantsdale-G will allow for multiple monitor configuration. Although on-board graphics are generally scoffed at by power users, the Intel® Extreme Graphics 3 will include Pixel Shader 2.0 which will allow it to fully support the new GUI interface of Microsoft's forthcoming operating system codenamed "Longhorn".

• LGA-775 "Socket T"
• 800MHz. FSB
• Hyper-Threading
• DDR-II
• PCI Express x16

ICH6 /  ICH6-R / ICH6-W (Southbridge)

With all of the new Northbridge chipsets arriving, Intel® has also worked hard to bring it's Southbridge partner up to speed. Intel has not one, but 3 new Southbridge chipsets to satisfy your every need. The most basics of the three chipsets is the ICH6. The ICH6 includes support for 4 Serial ATA ports and 1 single UltraATA/100 channel. The ICH6 has support for 4 PCI Express x1interfaces as well as continuing to support PCI.

The ICH6-R is the follow on to the ICH5-R chipset which was the RAID version of the previous Southbridge unit. The difference in the new chipset is that they have added more RAID modes, now RAID 0, 1, and 0+1 are all supported, thanks to a doubling of the previously available Serial ATA ports.

With the addition of the ICH6-W, you gain the benefit of built in wireless connectivity. Tri-band support is fully implemented with 802.11 a/b/g all available to the user.

All of the ICH6 chipsets will feature Intel® High Definition Audio (previously known as Azalia) which is the replacement for the AC'97 motherboard audio specification that we've all become familiar with over the years. This is much more than a mere sound chip though as it is designed to be an interface for virtually all media codecs on the system, from audio to DVD, Intel's® new specification is going to handle them all. With sound said to rival Creative Lab's Audigy2 card, Intel may end up upsetting audio vendors when customers who would normally invest in external devices end up satisfied with the quality and flexibility of their onboard audio.

• 4 SATA Ports
• 1 Channel UltraATA/100
• 4 PCI Express x1
• PCI Support
• Intel "Matrix RAID" = RAID 0, 1 (ICH6-R only)
• Wireless 802.11 a/b/g connectivity (ICH6-W only)
• Intel® High Definition Audio Spec.

Grantsdale-GV and GL

Looking further into the future, in Q3 of 2004, Intel® will be introducing the cost-sensitive chipsets based on the Grantsdale core. The Intel® Grantsdale-GV (i915GV) will essentially have the same features as the Grantsdale-G chipset, but with one major exception. The Intel Extreme Graphics 3 on the motherboard will be the only graphics available. Unlike the Grantsdale-G there will be no option to use external PCI Express x16 graphics.

The Intel® Grantsdale-GL (i915-GL) motherboard will be almost identical to the Grantsdale-GV, with the exception of CPU support. The Grantsdale-GL is designed for use with the Intel® Celeron processor with the Prescott core and a 533MHz. FSB. Budget-minded users would be wise to look to this board for their basic system needs, with the Celeron processor and the value chipset, this should make a very attractive price-point possible.

• LGA-775 "Socket T"
• 800MHz. FSB (533MHz FSB for the Grantsdale-GL)
• Hyper-Threading
• ECC DDR-II