you will want an i7-4790K, even if only 8gb ram. you can always add ram later, just be sure to get a mbd with 4 memory slots.
if you must go i5 for budget, then you might be better with amd fx-8350 or fx-8320. cheaper but somewhat faster.
i would run os/apps/cache/scratch on ssd, and install the 1tb internal for pagefile/storage/media. 2tb external for backups.
might consider buying a 2tb instead of the 1tb if finding a good price.
I can make some suggestions--need to know the OS you will run---has to be 64 bit though.
Also some fast thought are: I am pretty sure that Intel Xeon E3's are close to I5/i7's are far as CPU's price additionally if you have already decided on the I5's I7's look for the 2nd 3rd edition models they should be better priced because at present the current model are termed the i5/i7 4th generation--difference from previous generations are thinner, less power consumption less cache--really not much! I am pretty sure the same is true if the Xeon E3 and E5's In fact the 3rd Gen I5/I7 is what I would look for and buy. I got more ideas but gotta get back to work now.
FYI that link from tweakers from smith is NOT 100% accurate--when it says xeons don't run on anything other than server( in the E5's 26XX) software--the fact is for the E3's it will run just about anything os/netos wise and E5 with some tweaks is the same.
"I can make some suggestions--need to know the OS you will run---has to be 64 bit though."
I plan on running Windows 8.1 until Windows 10 comes out. Then I will upgrade to Windows 10.
I would think about getting a new Ssd, like the samsung 850 pro series with 256 gb for OS, cloud, pagefiles. 128 gb will be a bit short. Then set up your old ssd for Cache&previews. Have the 1tb for Media and projects. One advise here, 7,200 rpm is recommanded for video editing. I also think you shall run at least 16 gb of ram. In bigger projects ram would be your first bottleneck.
"Then set up your old ssd for Cache&previews."
I think maybe you misunderstood. I am asking about a computer I plan to build. I have bought nothing yet. The configuration above was just an idea. I'm wondering what you guys think is best.
If you build from scratch, a suitable set up might be:
16 GB RAM
256 GB 850 Pro SSD for OS, pagefiles
128 GB 850 Pro SSD for Cache & Preview
WD black 2 GB in RAID 0 for Media files, Projects
750 watt PS
When running CS6 get a nvidia gtx 760. For cc 2014 a 970.