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.

Comments

Take the PCIe logo off the box

[CajunArson]

These cards may or may not damage your motherboard, but there is zero doubt that in the default configuration -- not some out of spec hacked BIOS configuration -- they are not compliant with the PCIe standards.

Putting that PCIe logo on the box is therefore deceptive marketing and AMD should be held accountable here.

Re:Take the PCIe logo off the box

[CajunArson]

The new drivers in the default configuration are still out of spec with PCIe.

The fix that AMD applied is to route more power from the 6-pin PCIe power cable to reduce the power drawn from the motherboard. The motherboard is now supposed to be in-spec (of course, independent testing is necessary) but by defintion the 6-pin PCIe cable, which was already providing more than the specification-rated 75W, is definitely out of spec.

Now as a practical matter, the extra power draw through the 6-pin cable will not cause problems with any halfway decent PSU. However, just saying "oh it won't damage your computer in a practical scenario" is not the same thing as complying with the PCIe specification. Actual compliance with PCIe is required to show the logo on the box and advertise compatibility.

The fact that there is now going to be a non-standard "optional" mode that complies with PCIe is nice, but unless it's the default mode out of the box, it's not enough.

Re:It is hard to imagine that AMD missed this...

[Anonymous Coward]

they didn't miss anything
this is one of those cases where the spec is wrong
you CAN safely draw 100W from the PEG slot
you CAN safely draw 170W from a 6Pin (worst case crappiest psu on the planet scenario)

every single high end card on the market takes the PCI-e spec and throws it out the window frankly

the issue was blown out of proportion by a few users that knew nothing of which they spoke and stated it as fact