eerrm, thats actually not true, by the very nature that a dos os system has to break programme in to usable kernels as it cannot run single programmes larger than 640k due to the position of its Graphics card at A00000 -D000000 (this has not changed since the 70s, and was decided by IBM, who still own the patents on the board architecture, that why PC are referred to as clones) and then link these programme portions via Dynamic Link Libraries (DLLs) means that its processor overhead is vastly larger than a similar size in a Mac (these run a programme as a single programme) this is the main reason that graphics, and core data processors like using a mac. It doesn't run out of system resources just by running the OS and a couple of programmes which uses protected mode to limit each programme from using to many system resources. So cycle per cycle of processor function the Mac can devote more to the actual execution of the programme and data being worked on and with. so is faster.
THis is not a fan boy version. this is a computer system engineer benchmarked fact.. THat why we would never run real time data polling on PCs they just ran out of resources, and just couldn't handle it and run windows as well, unless we ran totally in DOS.
I will concede that Mac are not games machine, however the main reason for this is the lack of games publishers wanting to foot the cost of re-writing their games on two different platforms. But saying that, most Mac users are not as much into games, more into graphics and music. It is worth noting that during my time working in the industry I was often at games developers, and surprising all the PC games were actually written on Macs!!
Da