PC motherboards - technical definition

Following is a list of motherboard types and form factors that have been used in PCs since the first IBM PC in 1981:

                 Maximum Size
 Year            Width-Length
 Intr. Type      In Inches

 BTX (Balanced Technology Extended)
 2004  BTX       12.8 - 10.5
 2004  microBTX  10.4 - 10.5
 2004  picoBTX    8   - 10.5

 ATX (Advanced Technology Extended)
 1999  FlexATX    9   -  7.5
 1997  microATX   9.6 -  9.6
 1996  Mini ATX  11.2 -  8.2
 1995  ATX       12   -  9.6
 1995  EATX      12   - 13     Extended ATX

 LOW PROFILE (Expansion cards plug into riser)
 2002  EmbATX     9.6 -  9.6   Embedded ATX
 1997  NLX        9   - 13.6   NLX=New Low Profile
 1987  LPX        9   - 13     Western Digital
 1987  Mini LPX   9   - 11     Western Digital

 MISCELLANEOUS
 2002  Mini ITX   6.7 -  6.7   VIA Technologies
 1998  WTX       14   - 16.75  Workstation TX

 FIRST PCs
 1987  Micro AT   8.5 -  8.5
 1987  Baby AT    8.5 - 13
 1984  AT        12   - 13
 1981  PC/XT      8.5 - 13