Balanced Technology Extended (BTX) integrates cost-effective engineering and design strategies for power dissipation, structural integrity, acoustic performance, and motherboard design into a scalable form factor. The BTX specification was introduced at Intel Developer Forum in Autumn, 2003. Compusys are currently putting the new systems through our own extensive testing and anticipate having systems available to customers by the end of March.
Below you will find information about the form factor, why it was developed, and what new ‘ingredients’ are needed
Why Balanced Technology Extended (BTX)?
The current industry standard, ATX, was introduced in 1995, and the Balanced Technology Extended (BTX) form factor specification was developed as an evolutionary follow-on to the ATX form factor to address these new difficulties, and Intel expects it to eventually replace ATX as the industry standard.
|
ATX Challenge |
How BTX Addresses the Problem |
|
Limited Scalability |
Improved Scalability |
- ATX does not scale well into small form factor (SFF) designs
- Core layout in FlexATX exceedingly difficult
- Custom SFF designs are generally expensive and often exclusionary
- Performance silicon often excluded
|
- System ‘ingredients’ with standard interface definitions in a broader range of sizes
- Two Standard Thermal Module designs
- Three standard board sizes with common core area design.
- pico Balanced Technology Extended (picoBTX) – 1 expansion slot
- micro Balanced Technology Extended (microBTX) – 4 expansion slots
- BTX – 7 expansion slots
- LFX12V and CFX12V added to the existing standard Power Supply portfolio to support Small Form Factor PCs
|
|
Expensive to cool |
Superior Thermal Environment |
- Increasing system thermal demands can require substantial R&D investment in new heatsink and voltage regulation technologies and extensive chassis modifications.
|
- High power components use the same in-line, high velocity, low temperature airflow
- Above and below motherboard airflow helps improve voltage regulation and socket capability
|
|
Increasing Noise |
Superior Acoustic Performance |
- Increasing system thermal demands generally require more and noisier fans.
|
- Only two fans required - even in high performance configurations -Thermal module fan and PSU fan create and manage simplified system airflow
- Lower impedance and high velocity, low temperature air allows lower fan speeds
|
|
Motherboard Design complexity |
Improved Motherboard Design |
- Routing and component placement in ATX becoming increasing complex:
- Core routing area saturated
- Processor power delivery placement constrained
- ICH-to-I/O routing length
- MCH-to-memory routing imbalance
|
- More room for power delivery and rear panel I/O
- Balanced memory and localized I/O routing
|
|
Limited support for heavy heatsinks |
Improved Structural Integrity |
- ATX platforms limited to 450 gram CPU heatsink mass.
|
- 100% increase in allowable CPU heatsink mass (900g)
- Single, reusable ingredient (Support and Retention Module) used in all system sizes
|
|
Increasing cost to keep up with thermal requirements |
Improved Cost Structure |
- ATX power delivery, power dissipation, and motherboard design liabilities increase cost:
- New heatsink technologies
- New voltage regulation technologies and increased component count
- Chassis modifications
|
- Low temperature, high velocity airflow allows simpler, less costly heatsink technologies
- Standard ‘ingredients’ replace custom ‘ingredients’ for compact system designs
|
‘Ingredients’ for Balanced Technology Extended (BTX)-based Systems
Building a Balanced Technology Extended (BTX)-compliant system will require some new ‘ingredients’, designed specifically to support the BTX form-factor. Below is an introduction to the ‘ingredients’ that differ from those typically supporting the ATX specification.
BTX Thermal Modules
In order to produce the in-line airflow which is the key to the many benefits of this new specification, the BTX form factor utilizes a new thermal module design, which combines a fan, heatsink and duct. There are two sizes specified.
- Type I (Standard height): Designed to support a broad range of system sizes from full towers down to small form factor (10 litres and higher).
- Type II (Low Profile): Designed to support ultra-thin, ultra-small form-factor systems (6-9 litres).
BTX-based Motherboards
The BTX-based motherboard layout differs significantly from ATX/microATX, and requires designs built specifically for BTX. BTX also allows for multiple board sizes utilizing a common core:
- picoBTX: maximum width 203.20 mm, up to 1 add-in card slot.
- microBTX: maximum width 264.16 mm, up to 4 add-in card slots
- BTX: maximum width 325.12 mm, up to 7 add-in card slots
BTX-based Chassis
Because of the changes in motherboard layout, the new form factor will require unique chassis designed specifically for BTX. It will be critical to select a chassis that supports the chosen board size. A BTX-compatible chassis will require built-in features to attach the Support and Retention Module (defined below). Additionally, a Thermal Module Interface may be required. This is a ducting feature connecting the front of the Thermal Module to a front vent. It is needed to ensure that airflow exiting the Thermal Module cannot re-circulate and re-enter the Thermal Module Interface opening.Support and Retention Module (SRM)
The SRM is a metal plate that is assembled to the chassis beneath the motherboard to provide structural support for the motherboard and retention for the thermal module. The SRM is expected to be shipped with BTX-compatible chassis.
‘Ingredients’ that are not BTX-specific
Many of the ‘ingredients’ currently used for ATX-based systems are also compatible with BTX-based systems. These cross-platform ‘ingredients’ include:
- Memory
- Hard Drives
- Optical Drives
- Floppy (and other 3.5”) Drives
- Add-in cards (PCI, PCI-Express)
- ATX12V Power Supplies (for 20L and larger systems)
- SFX12V Power Supplies (for 15-22L systems)
Support for these various ‘ingredients’ may depend on chassis configuration.
To find out more about this important development and how it can benefit your organisation then contact us on 01296 505321 or email information@compusys.co.uk and arrange for your free BTX demonstration at our production facilities. |