Balanced Technology Extended  (BTX) Platform Info

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• Intel Thermal Modules

• BTX Motherboards

• Intel BTX Processors w/ Type 1 Thermal Module (LGA775)

• BTX Chassis

• BTX 3rd Party Type 1 Thermal Modules

Starting in late Q4, 2004, distributors began receiving and selling products based on the BTX form factor. Since this is an entirely new product, we are going to present you with a brief overview which will allow you to better understand the technology behind BTX technology and all that it encompasses.

In the beginning

At the Intel Developers Forum in the Fall of 2003 Intel announced the specifications for the new scalable form factor, BTX. The BTX (Balanced Technology Extended) form factor was designed to provide better routing, thermals and structural support for upcoming new technologies. The new board layout and design allows the use of low profile case designs with better performing CPU's. The current ATX technology was introduced back in 1995, I think you'd agree that a lot has changed since then. ATX has been struggling to keep up with the power and thermal demands that have been placed on it since the advent of the P4 and the time has finally come to stand aside and let it's successor take it's place.

Why the need for a change?

While ATX had many improvements over it's previous technologies, it has reached the limit of what can be done to modify it's design in order to make new technology work. ATX form factor designs were never meant to scale to fit smaller applications, therefore any smaller system boards that were needed were difficult to lay out and costly to design. The BTX form factor was designed with scalability in mind. From the beginning it has been planned with 3 standard board sizes and 2 thermal module designs (type I and type II). Type I (Standard Height) Thermal Modules are designed to support system sizes ranging from full towers down to small form-factor (SFF) machines. Type II (Low Profile) Thermal Modules are designed to support ultra-thin, ultra-small form-factor systems.

BTX Board Sizes

microBTX 10.4" x 10.5" (264.16mm) Up to 4 Expansion Slots Arrived Q4, 2004 Thermal Module Type I	BTX 12.8" x 10.5" (325.12mm) Up to 7 Expansion Slots Est. Arrival Q2, 2005 Thermal Module Type I	picoBTX 8.0" x 10.5" (203.20mm) Up to 2 Expansion Slots Est. Arrival Q3, 2005 Thermal Module Type II

In addition to the scalability of the BTX form factor, many other issues have been addressed as well. With the increased power requirements of modern processors there have been several items that have needed to be changed. Increased power means increased heat. While looking at all of the options you now have available to cool modern systems, some of them have become ridiculously expensive. Besides the standard heatsink route, people have now began water cooling systems or even going as far as using peltier cooling, or even in some cases cryo cooling (recirculatory refrigeration). Granted, those last few methods are mainly for the die hard system cooling crowd, but even the most modest of power users has now taken to, at the very least, filling his case with extra fans to protect his computing investment. All of this cooling comes at a price... and I'm not just talking about financial. I've personally been guilty of adding so many fans to my case that it makes it practically impossible to sleep in the house at night due to all of the noise. BTX addresses both of these issues.

The sound of silence

Ok, well maybe it's not silence, but it's much closer than we have been in several years. One of the advantages of BTX design is the effect that it has on the thermals of the system allowing the air to flow better through the case due to the placement of the slots and the positioning of the cabling. The design of the board routes the airflow in the case from across the front of the board where the CPU is positioned,  then across the chipset and past the 16x PCI express slot then out the back of the case. Looking at the pictures below of the fan bottoms, you can see that the new Thermal solution has been designed to also provide a nice airflow under the motherboard to add additional cooling. Acoustically the new design is better because it only requires two fans, the thermal module fan and the power supply fan.

Intel Type 1 Thermal Modules - Included with Boxed BTX Processors

Low Profile thermal Fan	Type I mainstream Thermal Fan top	Type I Performance thermal Fan top
Type I Standard thermal Fan	Type I mainstream Thermal Fan bottom	Type I Performance thermal Fan bottom

Better routing through new technology

As was mentioned earlier, one of the problems with the ATX form factor design is that it does not easily lend itself to be modified for use in different (usually smaller) devices. The routing and component placement in ATX has become increasingly complex through the years as the need for different components have been added to the board. The area around the core had become saturated and there were definitely issues in the MCH-to-memory routing path. The BTX design has a clean ICH-to-I/O routing path, and has also increased the rear Panel I/O capacity and improved MCH-to-memory routing length. A fresh board design has allowed components to be placed in the most logical positions when considering power requirements, partner components, and thermal requirements instead of trying to stuff them in wherever they would fit on a crowded motherboard. There has also been a slight increase in board area when comparing microBTX to microATX or in comparing BTX to ATX. The core components are stable as you scale the board from picoBTX to microBTX, and onto BTX.

How about some products?

Below is a picture of Intel's D915GMH (Digital Office) motherboard, they will have a Digital home version also. You can see that the layout of the board is designed to provide alot better airflow. The memory has been moved to the left side of the board and is placed in a way that will help airflow also. BTX based boards will require cases that are made specifically for BTX form factor motherboards. When you are planning to put together a BTX system you need to make sure to get the right size case for the type of BTX board that you are planning to use.  

Intel Desktop Board D915GMH
(Digital Office Version)                                                                                        

     When Assembling parts for a BTX system, after the motherboard, CPU heatsink and chassis are selected, any standard parts can be used.

BTX Motherboards

Intel  BTX Boxed Processors  w/ Type 1 Thermal Module (LGA775)

BTX Chassis

BTX 3rd Party Type 1 Thermal Modules

Intel BTX Boxed Processors w/ Type II Thermal Module (LGA775 - Pico BTX)