As you already probably know and as we written earlier, AMD has implemented two different fixes that should lower the power drawn by RX 480 from PCI-Express slot, including a fix that automatically lowers the current drawn from the PCIe slot and the, so called, "Compatibility Toggle", which can be enabled in the Radeon Settings, which drops the power consumption even further.
According to tests done by Techpowerup.com, the driver fix works like a charm as it uses a feature of the IR3567 voltage controller found on all reference RX 480 graphics cards. Apparently, the IR3567 voltage controller has a neat feature which allowed AMD to adjust the power phase balance between the slot and the 6-pin PCIe power connector.
Even the promised performance improvements work as advertised as it offsets the performance impact when the Compatibility Mode is enabled. When compared to the older Radeon Software 16.6.2 drivers, the power drawn from the PCIe slot drops from 80W, down to a more reasonable 76W with the new drivers and 71W when the Compatibility Mode is enabled.
Of course, it also raises the 6-pin PCIe consumption from 82W to about 89W and 84W, respectively. The maximum power drawn from the slot hit 79W with the new drivers and 73W with the Compatibility Mode, something that any PCIe slot should cope with easily.
Although the issue was not that big since most motherboards were able to cope with additional power drawn from its PCIe slot, it appears that AMD was lucky enough that the fix was quite easy and the software team probably pulled a night shift or two to get the new driver out and solve the issue.
Of course, you should install the new drivers in case you are gaming on Radeon RX 480 as although it might not blow your PCIe slot it is always better to be safe than sorry.