of course i'd imagine that under the hood, the PC/OS would turn single thread code into multi core code automatically (if we even still needed multi cores), and it would also apply any possible hardware graphics acceleration automatically. with unlimited ram and speed, there'd be the resources necessary to do this, while presenting a single thread non-hardware-accelerated API to the application.
Of course you wouldn't need multiple cores - you have unlimited cycles so you couldn't do any more work than you are already doing because you do it all at once anyway.
Same with 'hardware accelerated' - the concept no longer exists. Your software executes instantly, you don't need to 'hardware accelerate' anything.
Everything is software.