So far the only published review with benchmarks is this one from Legion Hardware, with many others including Ryan's to follow as the benchmark monkeys are whipped to a furious pace. The initial results show roughly what has been expected, the R9 390X is roughly 10% faster overall than the 290X and about 6% faster than the base 390 model which itself is roughly 8% faster than the previous 290. The 380 shows a similar 6% gain over the 285 and performance wise can tie the GTX 960. Bear in mind this is very preliminary review, as time is needed to properly test and to overclock the cards, keep your eyes peeled for more reviews and cards from other sources.
"Firstly we would like to thank HIS for supplying their HIS Radeon R9 390X IceQ X2 OC 8GB, R9 390 IceQ X2 OC 8GB and R9 380 IceQ X2 OC 2GB graphics cards. The cooling performance of their IceQ X2 cooler was excellent on all three cards and they look very eye catching as well."
Here are some more Graphics Card articles from around the web: