I have an app, which is single-threaded. The source code is not available. The people who managed it before me didn't really understand the whole "single-threaded" business and bought a ridiculously expensive 24-core box. Of course, the performance didn't improve.
I am looking to increase performance. I've read that having a lot of cores actually decreases the performance of a single core.
So which CPUs are really good for single-threaded performance? Cost is no object. The chip should be x86 and x64 compatible.