What are the speeds of at atx btx and mini atx?

Answer:
These are form factors (size and shape) of motherboards you can plug CPUs into. They have no speed in themselves. For example, both ATX and micro-ATX (there is no mini-ATX) boards are available for most recent CPUs, making them the same speed with the same CPU.

The differences between them are more along the lines of the size of the case it will fit in and how many expansion slots they have.

BTX hardly exists anymore, it was a form factor proposed by Intel but cancelled in 2006.
If you are in the market for buying one of them, I suggest going for one of the common standards: ATX (standard desktop tower size) or micro-ATX (a bit smaller)
The two ATX standards are for all practical purposes the same except for the size and the number of expansion slots.

See related link for more form factors.
First answer by J-g-faustus. Last edit by J-g-faustus. Contributor trust: 44 [recommend contributor recommended]. Question popularity: 2 [recommend question].