We started looking at the low end of the spectrum and found such models as the AMD Sempron and the Intel Celeron D. In both cases, we decided against the cheapest models available, because you can get more powerful models and the latest processor cores for only a small additional charge.

AMD Sempron 3400+

There are various Sempron models still around that have the Manila core with either 128 kB or 256 kB L2 cache. If you have to decide between more cache or clock speed, we recommend opting for faster clock speed. Our choice was a Sempron 3400+, which has 256 kB L2 cache and runs at 1.8 GHz. For some reason, Semprons are more expensive in the United States than they are in Europe. Our particular model was priced at $70. We chose it because we did not want to spend $55 on the 1.6 GHz, 128 kB Sempron 2800+. In my opinion both choices are too expensive. An Athlon 64 3200+ at 2.0 GHz and 512 kB L2 cache would have been an even better choice, but the $80 clearly would have exceeded our price limits.

Intel Celeron D 352

There are several Celeron D processors that are still based on the 90-nm Prescott core. These can be recognized by their small L2 cache size of 256 kB. Since there are better models, we do not recommend buying the old version. The Celeron D processors with 512 kB L2 cache are not only slightly faster, they are also more energy-efficient, as they are based on the 65-nm Pentium 4 Cedar Mill core. The old one can be purchased for as little as $40, but it's worth spending $50 on a Celeron D352, which runs at 3.2 GHz. We paid $56 for ours.