I thought you said you knew about PCs??????
partitioning is one of the basics, what FS are you going to use, do you know the difference? what size partitions are you going to make, primary? extended? logical? how many do you/should you make?
Your initial thread was all about how much extra bang/buck you would get but without fine tuning the system you have no chance of it performing at its best. What about virtual memory? how big? what partition? fixed or variable?
These are just very basic Qs. without understanding what you are doing it would be like letting you tune a ferrari, yes it still beat a mini but by how much?
I'm genuinely not trying to be awkward here but it does sound like you haven't got the knowledge to make that kit sing as it should. THAT is the reason I suggested buying a properly built, preconfigured/installed system, someone who knows what they are doing will have done all this for you. THAT is also why sometimes they are a bit more than the cost of their parts. I've been messing with PCs etc for longer than I care to remember, I've invested time patience and effort in learning what I do(as have those who charge to build PCs). I'm all for you learning and there is no better way than doing something yourself but when you have a problem, instead of just coming on here and asking why not try and work it out for yourself. read round the subject, understand it then next time you will know what to do when faced with a slightly different set of circumstances.