GilaMonster (9/1/2015)
Thanks everyoneI'm leaning towards getting a 256 GB SSD for the OS and then 2 (or 3) 1TB drives for all the large stuff (databases, graphics resources for my 3D stuff, games, documents, videos, etc). The current desktop has 2 1TB drives in it and one very old 320GB (which still works fine surprisingly), and I've got a 1TB in the drawer that I bought intending to replace the 320 and never did.
The motherboard that Glenn recommended I get has *10* SATA 3 ports on it, so running out of ports won't be an issue, and the case has space for 8 3.5" drives.
Now, affording it all is another matter, as is finding the time to do all the rebuilding.
Gail, if you can swing the price, look at getting a board that will support a PCIe M.2 drive. I've got one, with a 256GB M.2, for my desktop machine and holy carp the boot time is silly fast. I used to have a 256GB SSD, it blows that out of the water. You give up a PCIe slot and possibly one other device (in my case the chipset-based USB3 and the lowest PCIe slot on the board)
When I first loaded the system, the longest part of the boot-up was the BIOS screen. Now it's probably a tie between the BIOS and the OS. I'd say less than a minute between hitting the power button and being able to log in (Win8.1 Pro)