ryandavismusic
Is it possible to buy a CPU with bad real time performance? At the start of the video it seems like he is saying that certain CPU's are better for DAW's than others but then never develops that point and goes into talking about how the different components can lock up your cpu instead.
As long as the CPU is fast enough to perform all its duties within the window dictated by the sample rate and buffer size, then the CPU is fast enough. What he's saying is that the CPU has many other duties that distract it from processing audio, and it's that extra overhead that determines realtime audio performance. Even the world's fastest runner will lose the race if he's required to bake a pie en route.
For example, a Pentium III is perfectly capable of playing back a 50-track song in your DAW - but not if you're playing Halo at the same time.
None of this addresses your first question, though, "is it possible to buy a CPU with bad real time performance?". I can't think of any CPUs currently being sold that would be incapable of suitable realtime performance. Or any modern CPUs that couldn't be brought to their knees by a bad system configuration.
BTW, an easy way to check how well your own CPU is keeping up is SONAR's CPU meter. You may have noticed that it has little or no correlation to the Windows CPU meter. That's because SONAR's meter is measuring how much time was needed to service the audio buffers. When it reads 50%, for example, it means SONAR was able to fill the buffer in half the maximum-allowable time. If your computer didn't have other tasks and could just do audio, you could run it right up to 100% without dropouts. If you get dropouts at 50% it means the CPU is way too busy with other stuff.