The value perspective
Welcome to our famous value analysis, which adds capacity and pricing to the performance data we've explored over the preceding pages. We used Newegg to price all of the drives, and we didn't take mail-in rebates into account when performing our calculations.
First, we'll look at the all-important cost per gigabyte, which we've obtained using the amount of storage capacity accessible to users in Windows.
At $210 online, the Red 4TB costs a fair bit more than the $170 Desktop HDD.15. The difference works out to only about a penny per gigabyte, though. That's less than the two-cent gap between the Red and Black 4TB, which sells for $290.
Finally, the mechanical drives exact their revenge on the SSDs. The solid-state drives have similar asking prices to the 4TB HDDs but only a tiny fraction of their storage capacity.
Our remaining value calculation uses a single performance score that we've derived by comparing how each drive stacks up against a common baseline provided by the Momentus 5400.4, a 2.5" notebook drive with a 5,400-RPM spindle speed. This index uses a subset of our performance data described on this page of our last SSD round-up.
The Red 4TB is a solid all-around performer; it's competitive with several 7,200-RPM models and comfortably ahead of the 5,400-RPM competition. The WD Black 4TB offers a nice step up, but it's nothing like upgrading to an SSD.
Now for the real magic. We can plot this overall score on one axis and each drive's cost per gigabyte on the other to create a scatter plot of performance per dollar per gigabyte. The best place on the plot is the upper-left corner, which combines high performance with a low price. We'll focus on the mechanical drives first. You'll see why in a moment.
The Red 4TB is quite a bit faster than the 5,400-RPM contenders for only a little more per gig. As a result, it occupies a nice spot on the plot. You could get higher performance from something like the Black 4TB, but you're going to pay for it.
WD's 10k-RPM VelociRaptors are definitely outliers. They occupy a sort of no-man's-land between traditional hard drives and SSDs.
Adding the SSDs to the plot throws off the scale enough to minimize the differences between the mechanical drives. This is why PCs are best equipped with hybrid configurations that combine separate system and mass-storage drives.