I'm very aware of the inefficiencies/inefficiencies and costs of Intel's lineup of CPU's. My particular case involves a motherboard that supports Celeron, Pentium 4, and Pentium D models. My dilemma is that my Windows 2000 machine utilizing my motherboard does not natively support Hyperthreading Technology on my Pentium 4 HT 672, but it does see the extra thread as a second CPU. However, I would rather have the best Pentium D this board can utilize, as it runs cooler, and I believe I have a better chance of not seeing system instability using a genuine dual core rather than making W2K try to utilize a fake core.