While there have been a lot of rumors about tight supply being caused by production issues, NVIDIA's financial results and this article seem to indicate otherwise. Video card makers including ASUS, Gigabyte, MSI and Colorful are all expecting to hit new highs in the third quarter, both in terms of unit volume and profit.
AMD on the other hand is described as defending its marketshare with the Polaris lineup, it seems to be holding its ground but Polaris isn't as big as a success as hoped. The company is seeing fierce competition from NVIDIA's Pascal lineup, and competition will heat up further with the arrival of the GeForce GTX 1050, which is expected at the end of September at the earliest.