[ltp] What is a Planar Board?

[anjin]

Greg Meyer wrote:

>I had some trouble with the USB ports on a T41 so I sent the machine in for 
>service, and it was returned to me a note that said the planar board was 
>replaced.  The service manual makes no reference to a planar board. 
>
planar board is ibm*speak for a motherboard
before the advent of PCI m-boards, there were MCA --Microchannel-- 
planar boards
like Sony Beta technology, MCA planars were a technically superior 
technology that died because IBM didn't know how to market them