I know at least four vendors who'd be more than willing to help you calculate it, but does anyone really know the total cost of ownership (TCO) of their storage? Too often, these calculations have about the same gravitas as when someone starts describing what they're worth "on paper."

Still, Compellent jogged my feeble memory that vendors still offer these things with a new TCO tool. In its basic version it asks users six questions about usable capacity, annual storage growth rate, percentages of active/inactive data, kilowatt hour charges, annual salary for a storage admin, and average cost of downtime.

Click, click, click, and what do you know? The Compellent SAN is cheaper than the garden variety out there. Uh-huh. Apparently a more advanced tool is available for free if you give them name, address, phone number, e-mail, etc. My hope is it's like that car insurance commercial where the best quote may be from a competitor. My worst fear is that tools like these are little more than lead-generation factories.

Dell, EMC, IBM, Oracle, and VMware all offer some flavor of TCO tool, and they're all pretty much the same. The issue of how much vendors stack the deck in their own favor we can leave for another time. I'm more curious to know what else goes into your calculations that vendors don't consider, or purposely overlook. Add a comment below, or if you want more privacy, hit the "E-Mail" button at the top of this page and write me directly.

We'll see if these vendor promises are worth the paper they'd be printed on.