Your question is originally asking for "hardware" redundancy, of which there is none. However, there is operating system and software redundancy built to alleviate hardware issues.
Typical computer based avionics like the EFIS must be FAA-compliant with ARINC 653. Of course, in an experimental aircraft, you could potentially get non-compliant avionics, but there's not much of a market for them.
ARINC-653 requires that there be an real time operating system layer implemented as a form of redundancy. This is a special "round-robin" form of operating system, which in layman's terms, means that the operating system will only spend up to a fixed amount of time on a process before hopping to the next one, meaning that a single process hanging will not halt the rest of the partitions. You might have a navigation process that dies, but the GPS process can continue to operate as it is in a separate partition. It also has partial requirements that partitions are not dependent on each other, but instead retrieve their data directly from sensors. This gives another layer of redundancy in case a dependency crashes.
Running three displays off one processor is ill-advised, and would never be FAA-compliant, but it is technically possible. You would however have to heavily modify the operating system, and the "Guest OS" (ARINC 653) layer.
I'm happy to go far more indepth into this on StackOverflow if you choose to ask a follow up answer there, but the technical specifications are a bit out of scope for the Aviation StackExchange.