eTeknix posted a review on the ASRock Extreme4 Z390 Motherboard
A quote from the article:
The Z390 launch has brought with it a vast range of new motherboards. While it’s no secret that they’re a bit of a refresh of Z370, they mostly are tweaked, refined, and offer a few extra features. These are the best of the best, and the new flagship series from each brand. With that, comes support for the new 9th Gen CPUs from Intel, although they will also work with 8th Gen CPUs too.ASRock Extreme4 Z390 Motherboard Review
The ASRock Extreme4 comes well equipped, featuring a Digital PWM and 12 Power Phase design. This bodes well for overclocking performance on our i9-9900K. It’ll support multi-GPU configurations, and super fast M.2 storage or Optane for a competitive system build. Those who want even more storage options, you’ll be happy to see 8 SATA3 ports, and plentiful USB Gen 1 and Gen 2 connections.
That’s backed up with the superb ALC1220 Audio Codec, Polychrome Sync RGB lighting, and a few other bells and whistles to please those building a well-rounded gaming PC.