The same, but black!
Last month AMD launched their new RX 590 based on the Polaris 30 chip. Essentially the same as the Polaris 20 chip, but on the newer Global Foundries 12nm process which enables the card to clock higher than the RX 580.
Sapphire took the opportunity to launch the Special Edition Nitro+ RX 590. This card fashioned a blue fan shroud (which had a mixed reception) but overall was a very solid product.
Today, Sapphire announced their new RX 90 Nitro+ OC 590, sporting a black shroud (much to my eyes relief). While the Special Edition definitely had a nice look to it, the black shroud of the newer model should mesh more evenly with more builds going forward.
For the sake of thoroughness, here is a list of specifications for the Nitro+
|Core Count||2304 (36 CU)|
|ROPs||32 (8x 4PPC)|
|Bus Width||256 Bit|