Choosing a Laptop Computer
Processor Type
I'll cut to the chase and state up front that for our purposes the best processors commonly found in laptop computers these days (pending widespread availability of low-power tri- or quad-core variants in portables) are the Intel Core Duo (Core 2 Duo, etc.), along with the newer dual-core Pentium E series and Dual-core variants of AMD's Athlon architecture — basically anything with "X2 64" in the name. We can touch on some of the other options but those two are going to be the hands-down winners for a highly portable real-time audio analysis platform.
The original Pentium 4 architecture has pretty much disappeared from the earth at this point (and good riddance, I say). The newer Pentium E's and "Core" series processors are different animals. It's my understanding that more recent Intel processor architectures actually have more in common with the Pentium 3 than the Pentium 4 in some ways, having descended from a chip originally designed as a low-power Pentium "4" mobile by an entirely different development team (who lacked the resources to throw out the baby with the bath water as Intel did for the flagship Pentium 4). But please don't quote me on that.
In any case, a Core Duo or dual-core Pentium E (particularly the E5xxx) clocked at 2 - 3 GHz actually runs rings around a dual-core Pentium D running at 3 - 4 Ghz, while also converting significantly less electricity into heat. The same is true of the AMD X2 series CPUs, although even the higher-end AMD chips seem to be lagging behind the newer offerings from Intel at this point.
Intel Centrino (not to be confused with Celeron) isn't actually a processor, it's a marketing program. To qualify for the Centrino logo a machine has to use a specific combination of Intel processor, chipset and wireless networking adapter. Newer Centrino machines will likely have a Core Duo or Solo processor. Older machines carrying this brand and possibly some current down-market models as well might have a Pentium M (forerunner of the Core series) or a full Pentium 4 (gack!) CPU, so make sure you know what you're getting.
Celerons? Just say no. The Intel Celeron manages to combine most of the flaws of the original Pentium 4 architecture with few of its benefits. Oh, maybe that's not entirely fair. I guess they're fine for some things, just not Smaart. The biggest problem with the Celeron from our perspective is that it was designed primarily for business computing and lacks the Streaming SIMD extensions (SSE) found in the full Pentium and Core series processors. SSE is one of the things that can make Smaart go significantly faster, both for processing FFTs and in the case of older versions of Smaart (et al) graphics. So that's a obviously a major drawback in our little corner of the computing world.
Intel Atom CPUs? I have no personal experience with the Atom series processors from Intel but from judging from spec's and benchmark results, it looks they arguably ought to run Smaart about as well as a similarly clocked Pentium III, which is to say, better than a similarly clocked Celeron but that's seting the bar pretty low. Atom does have SSE at least. One significant drawback (for our purposes) that the Atom CPU is going to share with the Celeron however is that they are both found pretty exclusively in lower end systems featuring chipset graphics with shared graphics memory. (More on that in a moment.)
AMD's Sempron looks to be pretty comparable to the Atom, reprising the comment about low end systems, chipset video, and sharing system memory for graphics processing. Here again I'm relying on spec's and benchmarks in making this assessment. I've never actually laid hands upon a Semperon-based machine.
