The software will have to support distributed rendering, and Leo doesn't believe that Handbrake will do this. Apple's Compressor (in the Mac app store) that comes with Final Cut Pro can do this, and higher end pro products will allow the use of multiple machines to speed up the process. Rendering, or transcoding, can be sped up by distributing bits of the render to multiple computers across the network which they call a "render farm". The software would have to do the coordination of this. Leo thinks that Gary would be able to speed up the video encoding speed of Handbrake just by getting a newer Mac. Leo says to also look at the SSDs (solid state drives), and Macbook Airs do come with this. It turns out that speed isn't just related to processor speed as much as read/write speed to the hard drive, and an SSD would improve that.
Handbrake is multi-threaded, but that doesn't mean it supports "clusters" (using processors from multiple computers). Multi-threaded means that on a single computer it will use as many threads as the processor is capable of. Gary will benefit from having a faster processor with more cores. That's what newer computers offer, with the Intel i5 or i7, there may be 2 or sometimes 4 processors on a single chip. And each of those processors, with the i7, are multi-threaded and can do two things at once. So a 4 core i7 processor is doing 8 things at one time, which is like having 8 computers working.