You don't really have to do much in BOINC. It does automatic benchmarking to decide what your computer is qualified for. Select all projects if you want.

Beyond that, you are certainly allowed to pick and choose projects. If you only run one or two, checking the box to send other projects if your main project(s) runs out of work (or is unqualified) is recommended.

The African Climate Project depends more on a broadband connection (which is still automatically detected), because the workunits are very large, on the order of 10 megabytes each.

The projects here are heavy in floating point computation. HT (Hyperthread) Intel computers thrash around a lot with HT turned on because they have two fixed point registers, but only one floating point register. BOINC will also automatically run parallel workunits in native dual or quad core computers

They don't use any special graphics card capabilities, etc.

Thanks for all the advice! I had noticed that BOINC benchmarks integer and floating point performance, but I didn't know if it actually made use of it in deciding which work units or projects to run.

You mentioned 64-bit vs 32-bit Linux. What about OSX Leopard? The Intel Macs, or at least mine, are Core 2s, and supposedly the OS is now natively 64 bits though I haven't tested it yet. Do any projects actually run in 64-bit mode?

As I recall, the Core 2 operating in 64-bit mode provides twice as many SSE registers as in 32 bit mode, and that could be a significant benefit to many projects.

--Phil