The launch of AMD's latest graphics card last week was a big thing in the tech industry: $US199 (or $320 at its cheapest here) for a card that can handle VR, while comfortably handling games at 1080p and even 1440p in some situations.
But it's not all good news. Apart from some bruised expectations, some reviewers also noticed that their sample cards were using a little more power than they were supposed to. The drama broke out late last week and it wasn't until the polls had closed Australian time that AMD had finally answered.
Before we get into AMD's statement, here's a quick recap.
As all graphics cards do these days, AMD's RX 480 connects to the motherboard via the PCI Express (PCIe) slot. It also uses a 6-pin power connector, which is indicative of the power savings from AMD's previous cards — they used an 8-pin and a 6-pin connector.
So far, so good. Flashy new GPU from AMD plugs into Ordinary Power Supply with one connector instead of two. Here's what that looks like.
That's the 8-pin connector you can see sticking out there. But the difference between the connectors is actually important, and that's part of the problem.
According to the official specifications for PCIe, the 6-pin power connector is allowed to draw up to 75 watts (W) of power. The 8-pin connector is supposed to only draw up to 150W. (Manufacturers can obviously draw more power than that, but they're not compliant with the PCIe spec if they do.)
So the RX 480, which only uses a single 6-pin connector, is only supposed to pull up to 75W from the PCIe slot. And some reviewers, such as Tom's Hardware, discovered that it didn't.
Now you might be asking: sure, it draws a bit more power than it's supposed to. What's the deal? After all, it's not like it's using 1000W of power or something. Most people's power supplies can handle that no trouble. And it's certainly not going to add to your power bill right?
All of that's true. But there's a reason the PCIe specification sets limits on how much power can be drawn. Pull more power than you're supposed to and you'll put additional strain on the motherboard — strain that it might not be capable of dealing with. Here's Tom's Hardware on the issue:
Believe it or not, the situation gets even worse. AMD's Radeon RX 480 draws 90W through the motherboard’s PCIe slot during our stress test. This is a full 20 percent above the limit. To be clear, your motherboard isn't going to catch fire. But standards exist for a reason. All of the components around the PCIe slot and along the path from the slot to the 24-pin ATX connector will suffer from the peaks. And depending on your platform's design, audio problems may also materialise.
On top of that, multiple sites also noticed that the RX 480 was exceeding the Thermal Design Power (TDP) that AMD announced for the RX 480. The TDP is basically the maximum amount of power, in this instance a GPU, will use under regular usage.
The RX 480's quoted TDP was 150W, which is referenced in their official releases and slides. A few sites noticed the RX 480 was hitting around 160W or 165W. It's certainly nothing that users should be concerned about, and it certainly isn't going to put any of your components at risk.
But it's a bad look for AMD nonetheless. Everyone's used to companies tilting benchmarks their way. But specifications are more set in stone, and it's another annoyance to those who were hoping for the RX 480 to be more of a giant killer.
Now that we're all on the same page, here's what AMD has to say about it all.
As you know, we continuously tune our GPUs in order to maximise their performance within their given power envelopes and the speed of the memory interface, which in this case is an unprecedented 8Gbps for GDDR5. Recently, we identified select scenarios where the tuning of some RX 480 boards was not optimal. Fortunately, we can adjust the GPU’s tuning via software in order to resolve this issue. We are already testing a driver that implements a fix, and we will provide an update to the community on our progress on Tuesday (July 5, 2016).
Converted into Australian time, and with tomorrow being Independence day in the United States, it means we won't see any official updates or driver hotfixes until at least Wednesday afternoon.
So let's come back to reality for a bit. For those who forked out for a reference RX 480 before the end of the financial year, should you be concerned about damaging your motherboard?
Not really. It's difficult to note how widespread the issue was amongst samples that AMD sent out to reviewers, because not everyone has the equipment to directly measure the power being drawn. But amongst those with the capacity, not everyone had the same issue.
If your card was consistently drawing more power than it should over a long period of time, then the likelihood of something failing would be greatly increased. But a hotfix will likely be out before a lot of Australians even take receipt of their RX 480, given that pre-orders for them only opened late last week.
It's not exactly a storm in a teacup, but it doesn't look good for AMD either. We'll keep you posted later this week when the new Crimson drivers become available, along with anything else the company has to say on the matter.