Hardware Reference
In-Depth Information
core processor designs has slowed the need for the benefits inherent in the BTX standard,
whichhasinturnslowedtheadoption ofBTX,causing Intel toannounce inlate 2006that
it was abandoning future BTX development. BTX was popular in many mass-produced
retail-branded PCs sold between 2005 and 2007, such as those by Dell, Gateway, and oth-
ers. Since then the BTX form factor has largely been abandoned.
BTX is not backward-compatible with ATX or other designs. A full-size BTX board is
17% larger than ATX, allowing room for more integrated components onboard. The I/O
connectors, slots, and mounting holes are in different locations than with ATX, requiring
new chassis designs. However, the power supply interface connectors are the same as in
thelatestATX12Vspecifications,andnewerATX,TFX,SFX,CFX,andLFXpowersup-
plies can be used. The latter two power supply form factors were specifically created to
support compact and low-profile BTX systems.
The primary advantages to BTX include optimized inline component layout and routing,
optimized airflow path, a support and retention module (SRM) for heavy heatsinks, scal-
able board dimensions, low-profile options, and flexible power supply designs with con-
nector types that are compatible with ATX designs.
BTX includes three definitions of motherboard size, as shown in
Table 4.1
.
Table 4.1 BTX Motherboard Form Factors
Each board has the same basic screw hole and connector placement requirements. So, if
you have a case that fits a full-size BTX board, you can also mount a microBTX or pi-
coBTX board in that same case (see
Figure 4.10
)
. Obviously, if you have a smaller case
designed for MicroBTX or picoBTX, you won't be able to put the larger microBTX or
BTX boards there.
Figure 4.10
BTX specification 1.0a motherboard dimensions.
