Another thing to consider if you are building this box yourself is the case you plan to use. Air flow for cooling is very important, don't forget that. Most older CPUs generate more heat for the same workload. Also, the most expensive item in the setup is the hard drives for most people. These are expected to fail after ~3 years (most last longer, my drives just past the 4.5 year mark of operation and that is full time spinning) but it's money that you know you will need to spend again. The motherboard, CPU, RAM, PS, and Case are items you expect to last 10+ years (well I do). Make these a good purchase because you will live with them for a long time. If you try to bargain shop for these items and cut corners like getting a lesser CPU, you may hate yourself later. Try to figure out exactly what you want to do with this box and buy the parts so you can achieve this.