Testing AMD’s HD 7970M Enduro Hotfix

I just posted the full review of the Clevo P170EM from AVADirect, but there’s a ton of content specific to the Clevo notebook and I know many of you are waiting to hear more about AMD’s Enduro 5.5 driver updates. Let me start by pointing back to our overview of AMD’s Enduro technology. I had some back and forth discussions with AMD, and that took long enough that the public Enduro 5.5 update is now available. As I noted in the beginning of the first Enduro article, my initial impressions weren’t particularly good to say the least, and my first encounter with the P170EM didn’t assuage my concerns. Thankfully, AMD has been working to improve/fix the technology, and the public Enduro 5.5 driver at least installs and updates the UI for Enduro, with the promise of future driver releases.

There were many comments on the Enduro article, and in general most of those comments weren’t particularly favorable towards AMD or the HD 7970M, but my experience suggests that (nearly?) all of the problems can be fixed with driver updates. One complaint in particular is with GPU underutilization—that the 7970M in some games is only running at 50-70% utilization, and thus delivers lower than expected frame rates. The public 12.9 Beta drivers still have this problem in many games, but AMD knows this and is working to fix things. Let me first describe what’s happening before getting to the fix.

When you max out the details in most games the 7970M will still get above 30FPS, which is good. Unfortunately, in some titles the GPU utilization will drop well below 90% (around 60% in some games) and this results in a very perceptible drop in performance. So for example, a game like Battlefield 3 might go from a smooth 40+ FPS down to 20FPS for a second or two, then back to 40+ FPS—lather, rinse, and repeat. As you can imagine, that makes serious multiplayer gaming a real problem, and at lower detail settings (with higher frame rates), the GPU utilization is even worse (sometimes even lower than 50%). Going through our current gaming test suite with the public drivers, in some of our test titles we only get slightly improved frame rates despite dramatically lower complexity. Owners of 7970M notebooks have expressed a great deal of frustration with AMD over the situation, and the lack of driver updates has only heightened the irritation.

Thankfully, AMD is set to address the driver updates issue with their new Enduro Catalyst program. What’s more, AMD is aware of the GPU underutilization problem and they’re working to address that as well. The initial 12.9 Beta driver still has underutilization problems, but AMD plans to release a Hotfix in the next week or so that should hopefully clear things up. Whatever the root cause (possibly the problem is related to the copying of frames over the PCIe bus, as the problem becomes more pronounced in games that hit higher frame rates), AMD says the issue can be fixed with drivers. To prove this, AMD gave us advanced access to the Hotfix drivers, and we’ve run them with our current test suite. You can see the full performance breakdown in the Clevo P170EM review, where we look at performance with three sets of drivers to show how things have/haven’t changed since the 7970M launch, but we wanted to provide a short summary outside of the notebook review.

The above table compares the Hotfix performance to the best result from the previous two drivers (e.g. the initial Clevo P170EM driver from May and the Catalyst 12.9 Beta from last week). The 12.9 Beta actually tends to be the lowest performing driver out of the three we tested in most games, but it’s usually relatively close to the original driver. The Hotfix on the other hand only shows one drop in performance: Batman at Enthusiast settings is down from the Beta, which in turn is down quite a bit from the original driver. Everywhere else, the Hotfix is at least equal to the better of the previous two drivers, and in many cases it’s significantly faster. It’s especially potent at lower quality/resolution settings, where we see an average increase of around 30% at our Value and Mainstream settings. At maximum quality for our six titles (since Shogun 2 won’t allow the Very High preset), the average increase is only 7%, but if we eliminate Batman it’s a 13% increase. That still doesn’t really tell the whole story, however, as performance was actually good in many titles but needed help in a few others.

If we take a closer look, Battlefield 3, Civilization V, DiRT 3, and Shogun 2 all show >40% improvements at our Value preset, and the same set minus BF3 sees big gains at our Mainstream preset. At our Enthusiast settings, however, only Civilization V sees a major increase in performance. That sort of performance jump is huge—GTX 680M for instance is only around 50% faster than the previous generation GTX 580M on average—but of course we’re really talking about HD 7970M performing poorly at launch and getting fixed (and I believe most of this is specific to Enduro enabled 7970M notebooks like the Clevo P150EM and P170EM).

All of this goes back at least in part to the GPU underutilization issues seen with earlier drivers, where higher quality settings/resolutions are more likely to stress the GPU. We did check GPU utilization with the Hotfix on all of the tested titles, and there are still games where we see sub-80% GPU use (particularly at lower details/resolutions), but I’m not sure that’s particularly important when we’ve got competitive frame rates. Note also that as far as I’m aware, the GPU underutilization issue is confined mostly or perhaps even solely to the HD 7970M/7950M—the lesser GPUs like 7870M and 7770M should not experience this as much, largely because they’re not as fast and it will be easier to reach GPU bottlenecks as opposed to CPU limits.

We’re not done with the AMD Enduro driver story, of course. With this release, AMD is starting on the road to delivering reference drivers that will in theory work with all Enduro (PowerXpress 4.0 or later) laptops. In practice, there are still some teething problems, and long-term AMD needs to get all the kinks straightened out. They’re aware of issues with other Enduro laptops and the 12.9 Beta drivers (they’re beta for a reason, right?), and hopefully the next major release after the Hotfix will take care of the laptop compatibility aspect. I’ve stated before that AMD’s Enduro feels like it’s where NVIDIA was with Optimus about two years (2.5 years) back, and that continues to be the case. The first public Enduro beta driver is a good place to start, and now AMD just needs to repeat and refine the process a few more times. Hopefully by the end of the year we’ll see a couple more driver updates and compatibility will improve.

We’re also working to get the Alienware M17x R4 with HD 7970M, which will allow us to specifically see how much performance is affected when we enable/disable Enduro support. AMD’s target should be less than a 5% drop (basically similar to what NVIDIA achieves with Optimus), so if/when we can test a discrete-only 7970M implementation we will provide further details. In the meantime, if you simply must have an HD 7970M notebook, Alienware’s inclusion of software controlled muxes to allow the disabling of Enduro makes that the safest bet.