Entry level PCs can have lesser processors than mid-priced PCs of 4-5 years ago. This can affect your ability to use VSTi with low latency, no matter what speed your hard drive is. I know this from personal experience. I bought an entry-level Toshiba laptop that simply was not up to the task of low latency audio processing for VSTi and ended up returning it and buying a refurbed machine with a faster processor for about the same price as the Toshiba.

So, now when I upgrade PCs, I typically will buy a prior year model, with a faster processor, than the same priced model that is newly introduced. This is how I ended up with a Core i3 processor lappy last year, when Core i5 was what all the new entry level lappys had on them. I did some homework looking at benchmark scores and the i3 that I bought got much better scores than the i5 models coming onto the market at the same time.

Softsynth performance is very important to me, might not be for you. Unless the softsynth is sample-based, the hard drive speed is almost of no significance, but processor ability to make use of multiple cores, etc. can be much more important. If your main thing is demanding of hard drive performance, like extensive use of RTs, then hard drive or even SSD speed probably trumps processor speed.

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