Originally Posted by
DozyWannabe
Airbus/Boeing FBW systems use hardened versions of obsolete commodity hardware - the suppliers won't stop making them as long as there's a demand.
To add to this, there's also the ability to create a hardware abstraction layer (similar to virtualisation) which allows you to swap out the underlying components whilst maintaining a uniform look and feel to the systems they support. I would expect (if it's not already being done) this to be one of the drivers for newer aircraft, as they can then forklift the proven systems from one aircraft type to the next, and provide redundancy/resilience and obsolescence-proofing.