[coreboot] Will a KCMA-D8 boot without the 8pin EPSV12 cable if you are using a 35W CPU?

Nico Huber nico.h at gmx.de
Fri Oct 19 11:15:18 CEST 2018

On 10/18/18 3:16 PM, Angel Pons wrote:
> I believe the power traces are different, so the CPU VRM feeds only through
> the EPS12V connector. However, if your PicoPSU is large enough, I guess a
> EPS12V cable can be attached to it.

Probably not for a 35W CPU, but generally: Using adapters for the
EPS12V connector is dangerous. They have more than two pins for a
simple reason: The electrical current through each pin/connection must
not get too high. There are adapters that route the whole current
through a single pin on the other end (e.g. a single old-school PATA
drive connector). Never use these unless you know they can take the
current you expect! (e.g. not much more than 3A for a 35W TDP, that
might be ok for a single pin, but you should read each connectors

Same applies to the tiny connectors for (hard)-drives on the PicoPSU,
if the current goes through less pins on the PicoPSU side, don't do it
(unless you know what you are doing).

There are PicoPSUs that have a 4-pin EPS12V connector btw. So I'm not
sure what the original question was; would it work w/o full 8 pins? or
would it work w/o any? The former likely yes, the latter likely no.


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