2U 3U 4U Servers

[PoopyPants]

Can someone throw me a bone here. What is the U in 2U 3U 4U servers
Ive also seen PSU's Labelled at 5U

what is the purpose and/or meaning of the U
is it Unit ?
is it Unexplanable ? lol
is it Universal ?

Is there a standard that follows the 'U' series of servers and products

Ive looked around but searching for 'U' servers just ends me up at a price point ie; a website selling them or spec's on a certain one, it doesnt say the meaning or reasoning behind the 'U'

 

[f95toli]

AFAIK U refers to size in this case. A 1U server is made so that you can rack-mount it in 1 19" rack, the height of the box is then 1U.
I don't remember how much 1U is but I think it is around 4 cm.

 

[skypilot]

1U is 1.75".... actually short for 1RU, which means "one rack unit"