The Guru of 3D published a review on the PowerColor Radeon R9 390 PCS+ 8GB
A quote from the article:
We review the PowerColor Radeon R9 390 PCS+ 8 GB Edition. The card's equipped with that renamed Hawaii Pro GPU, now called Grenada. It comes fitted with a massive triple slot air cooler keeping this product under 70 Degrees C, that's under full gaming load whilst being factory overclocked and fairly silent. The 2560 stream processor based Hawaii/Grenada chip will get paired with 8 GB GDDR5 memory running along a 512-bit memory interface. The card itself is fully customized including component selection, custom PCB, custom cooling, well... custom everything! Powered through 8-Pin + 6-Pin power configuration it obviously runs at factory overclocked specifications as well. The card will clock towards 1010 MHz with a memory clock at 6000 MHz (effective data-rate).PowerColor Radeon R9 390 PCS+ 8GB Review @ Guru3D
So to clear up some confusion from the get-go, this product is based on the Hawaii GPU released back in October 2013, the silicon is the same yet with a few tweaks applied the product is now called Grenada, the latest iteration of the asic. It is the very same 6 Billion transistor GPU on that 28 nm fab based 438 mm2 Die. Over time the fabrication will however yield better; much like fine wine the latest iterations of the silicon evolve, hence they can now be clocked a notch faster. The memory is tied to a 512-bit memory bus with one distinct difference, you now get 8 GB of graphics memory. That memory is tweaked and clocked a notch faster as well, 6 GHz (effective data-rate). The 390 GPU seated into this PowerColor PCS+ edition will get a clock of 1010 MHz. So, overall coming from the 290 you should see performance increases running up-to maybe 10% overall, depending on the card you purchase. With the recent focus on Ultra HD gaming, AMD is also marketing that to be pretty significant, hence that 8 GB of graphics memory. It's not new though as there have already been 8 GB SKUs of the 290 and 290X available for over a year, let's do mention that as well. The tweaks on the GPU and memory clocks however seem to be the biggest change, the rest is complimentary from the board partners. As stated, the PowerColor Radeon R9 390 PCS+ edition card is tweaked a little better for you, its GPU may run upwards to 1010 MHz with 6000 MHz (effective) on the GDDR5 memory.
The all custom PCB with Grenada is being cooled with a new model three slot triple fan cooler. The product remains fairly silent enough, in idle / desktop mode the fans won't even spin. You get color lighting options to change the logo to a color of your preference.