Just a point on EMC and OEM PC builds. The general assumption is if all the components are independently tested then the final assembly is as well. Under EMC Directive at least if all components are CE marked then job done. If your device is found not to be compliant then push the problem upstream.
No refering to you but the assumption- it's total
bullshit.
A. Components should not be CE marked (there are exceptions like safety switches, but not relevant here)
B. Unless you use the exact configuration used for testing you can't ensure compliance.
C. It is the manufacturer or importer who is responsible for compliance. If you/they get fined good luck trying to get the board suplier to cover your cost. You certainly can't pass the prosecution on to them, they will soon point out the components do not have to comply, see A.
D. How do you CE mark a case for EMC just sit it in a chamber with no power
(the case is vital to PC EMC)
Even if an OEM has correctly designed manfactured and test a product and it is compliant they have to show onging production is compliant. This included ensuring any changes in component specifications do not havee an adverse effect.
The big issue is there is virtually no enforcement and in th UK the agency charged with enforcement has no inhouse expertise or funding to get it.
There is a story that HP had trouble with EMC on some VME systems, reportd by he users. Long story short due to local regulations the grounding finger strip on front panels of cards made in europe had different plating to those from the USA. All EU or all USA card stups were fine but if you mixed cards there wew poor bonding and passive intermodulation problems! Even when you try hard it can still fail.