BTX (form factor)

Comparison BTX μBTX nanoBTX ITX picoBTX
BTX case of a Fujitsu Siemens Esprimo P2510
Clearly visible: the four holes for the "Support and Retention Module (SRM)"

BTX (for Balanced Technology eXtended) is a form factor for motherboards, originally intended to be the replacement for the aging ATX motherboard form factor in late 2004 and early 2005.

It was designed to alleviate some of the issues that arose from using newer technologies (which often demand more power and create more heat) on motherboards compliant with the circa 1996 ATX specification. The ATX and BTX standards were both proposed by Intel. However, future development of BTX retail products by Intel was canceled in September 2006 following Intel's decision to refocus on low-power CPUs after suffering scaling and thermal issues with the Pentium 4.

The first company to implement BTX was Gateway Inc, followed by Dell and MPC. The first generation of Apple's Mac Pro used some elements of the BTX design system as well, but was not BTX-compliant, instead using a proprietary form of a factor.