User der8auer has posted a guide in which he was able to unlock some of the AMD's RX 460 features with a BIOS update. The shaders are defaulted at 896 shaders / 56 TMUs but got unlockied to of 1024 stream processors and 64 TMUs. 

Here is the guide posted by him:

The AMD Radeon RX 460 unlocking process involves nothing more than a simple firmware update and can result in a performance upgrade of 12.5%. The Radeon RX 460 is considered a solid choice in terms of price/performance. It comes by default with 56 TMU and 896 Stream Processors in the form of the Polaris 11 GPU architecture. But here’s how to get an additional 8 TMUs and 128 Stream Processors.

Note: It’s always possible that something goes wrong if you flash the BIOS of your card. In addition it’s possible that not all cards can be unlocked and that you might damage the card. Flash at your own risk!

nlocking the RX 460 is pretty simple. It’s unclear why we’re able to do this. Has AMD locked the cards down on purpose, or are the yields not high enough to fulfill the Radeon RX 460 demand? Let us know in the comments what you think!

Currently we can only provide the BIOS for the Sapphire Nitro 4G and the ASUS STRIX O4G. We’re working on testing more cards and if it works, we will upload more modified BIOS versions. In total we have tested 6 cards, each of which was able to unlock the shaders. We tested five ASUS STRIX O4G cards and managed to unlock all five of them.

Download the BIOS package (currently only ASUS STRIX 04G and Sapphire Nitro 4G) and unzip the files.

First backup the original BIOS file in case you want to flash the card back at a certain point (run “backup bios.bat”). You can also save the BIOS with the latest version of GPU-Z. Afterwards run “flash unlocked bios.bat” to flash the bios. It will take about 15 seconds and should look like in the picture below.

AMD RX 460 Unlocked with BIOS Update - Offers 1024 instead of 896 shaders