You can often read that SSDs are 10X more expensive than HDDs but it’s not true anymore for recent flash drives – but for 3TB and more -, as, following the decrease and higher densities of flash chips, the prices of SSDs are decreasing sharply. Below 3TB its between 1.2X and 2.7X only in favor of HDDs. And some experts project that flash chips will be divided by two this year to better compete with magnetic units.
On the other side, the prices HDDs are decreasing very slowly. As an example, the average price of all HDDs sold by Seagate was $67 in 4FQ16 and $70 in 1FQ19. For the same two periods, it was respectively $63 and $72 for WD.
Today there is no more reason to buy HDDs of 500GB or less as SSD pricing is about the same or less with much better specs. That’s why there are very few HDDs of less that 500GB on the market.
Above 3TB and more, the situation is completely different with ratio of 10X to 23X in favor of magnetic devices (see the table below). That’s why now and in the future, HDD makers will concentrate only on high capacity 3.5-inch devices, quitting SAS and FC enterprise units as well as progressively giving up notebook rotating units.
Price of SSDs depends essentially of the number of flash chips integrated – you just have to add a controller -, but it is diminishing with the arrival of 3D NAND. HDDs have a minimum price with disks, heads, motors and controllers, the difference in capacity depending essentially on the number of platters (and then heads of both sides of them).
The arrival of helium, innovated by HGST, authorizes to add more platters, up to 9, in HDDs in 3.5-inch form factor only, and consequently to increase capacity, but here SSDs have the big advantage to occupy a smaller volume (7mm 2.5-inch) for their integration into computers and storage subsystems.
Below is a comparison between prices of both internal units (in 3.5-inch form factor for HDDs and 7mm 2.5-inch form factor for SSDs) as reported on the official web site of Western Digital or Amazon.
|Capacity||HDD model||Price||HDD price/GB
||SSD model||Price||SSD price/GB
||Ratio in favor of HDD|
|500GB||WD Black Performance Desktop||$66||0.132||WD Blue 3D NAND SATA||$80 (1)||0.160||1.2X|
|1TB||WD Black Performance Desktop||$76||0.076||WD Blue 3D NAND SATA||$150 (1)||0.150||2.0X|
|2TB||WD Black Performance Desktop||$115||0.057||WD Blue 3D NAND SATA||$310 (1)||0.155||2.7X|
|3TB||Seagate Barracuda||$63 (2)||0.021||Intel DC P4610 Series||$1,454 (2)||0.485||23.1X|
|4TB||Seagate Terascale||$70 (2)||0.017||Samsung 860 EVO||$699 (2)||0.175||10.0X|
|8TB||Seagate IronWolf||$238 (2)||0.030||Intel DC P4510||$2,957 (2)||0.370||12.4X|
(1) Official current prices on WD’s web site
(2) not refurbished units at Amazon