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AMD Details Driver Fix For Radeon RX 480's Controversial, Spec-Exceeding Power Draw (pcworld.com)
AMD's 150-watt Radeon RX 480 apparently draws more power than it is supposed to. According to Tom's Hardware blog, AMD's new graphics card used an average of 168W under load. Furthermore, the publication found that card pulled up to a whopping 90W over the motherboard's PCI-E slot, far exceeding the 75W maximum the slot it rated for. PC Perspective's findings were similar, with Witcher 3 title consuming over 190W of sustained power draw when the RX 480 was overclocked. Worse, the blog discovered that AMD's card drew 7 amps over the PCI-E slot's +12v rail, which is rated for 5.5 amps maximum. These issues could theoretically (but not likely) damage lower-end motherboards in extreme circumstances, writes PCWorld. The chip company last week addressed the concerns, noting that it will soon release a software fix. In a new statement to PCWorld, the company adds:"We promised an update today (July 5, 2016) following concerns around the Radeon RX 480 drawing excess current from the PCIe bus. Although we are confident that the levels of reported power draws by the Radeon RX 480 do not pose a risk of damage to motherboards or other PC components based on expected usage, we are serious about addressing this topic and allaying outstanding concerns. Towards that end, we assembled a worldwide team this past weekend to investigate and develop a driver update to improve the power draw. We're pleased to report that this driver -- Radeon Software 16.7.1 -- is now undergoing final testing and will be released to the public in the next 48 hours. In this driver we've implemented a change to address power distribution on the Radeon RX 480 -- this change will lower current drawn from the PCIe bus. Separately, we've also included an option to reduce total power with minimal performance impact. Users will find this as the "compatibility" UI toggle in the Global Settings menu of Radeon Settings. This toggle is "off" by default. Finally, we've implemented a collection of performance improvements for the Polaris architecture that yield performance uplifts in popular game titles of up to 3%. These optimizations are designed to improve the performance of the Radeon RX 480, and should substantially offset the performance impact for users who choose to activate the "compatibility" toggle.
Depends on the power supply, Most of them can run more than 75W on the six pin, as their 8-pin connector merges the extra grounds to the six-pin ground wires, which they simply beef up to take it. The 8-pin is rated for 150W, and the only difference with the 6 pins is 2 additional ground pins being added.
High powered? This is their budget card, not their flagship model (that has not been released yet).
Sorry, teleporters just kill you and then make a copy. A perfect, soul-less copy.
You're wrong again. The RX 480 uses the 6-pin cable as an 8-pin cable. It ignores the sense pin and uses it as a ground, which is how it is wired. This gives 3 pairs and allows you to pull as much as an 8-pin while still being in spec with regards to power draw, though out of spec with regards to implementation.
It's completely safe. It's not the first card to draw past spec on the 6-pin or 8-pin cables, and it won't be the last.
If you look at 6+2 pin cables on PSUs, you'll see that the +2 pins are simply extensions of the 6-pin plug. You're not getting more physical pairs in those 6+2 pin cables, yet you're drawing up to twice the current! OUT OF SPEC!!! DOOM AND GLOOM!!! Oh wait, it's completely fine.
Read the specs and look at the physical implementations.
Burned out PSUs instead of motherboards, here we come!
Exceedingly unlikely. The excess power draw through the motherboard was already being fed by the PSU.
Most PSUs have a single 12V rail that supplies all components in the system, including the motherboard.
As a result, the 12V rail is typically rated to supply most of the PSU's wattage. I would expect no issues unless the total system draw is near the PSU's capacity.
E.g., I have a 400W Seasonic PSU that can supply ~350W on the 12V line. I have an older GPU rated for 200W, and it has worked fine for years.
Swapping in the RX 480 with its 150-180W draw would cause no issues---especially after this driver fix. All power above the 75W limit for the PCIe slot will now be drawn from the ancillary power connector, as it should be. This is the same as previous cards, among them the 250-300W monstrosities marketed as Fury/Titan.
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According to the latest ruleset, this post should be modded as Vorpal Flamebait +5.