Mobile GPU Faceoff: AMD Dynamic Switchable Graphics vs. NVIDIA Optimus Technologyby Jarred Walton on September 20, 2011 6:40 AM EST
This has been the first laptop with AMD switchable graphics that I’ve had a chance to actually review, and it hasn’t impressed me as much as I would like. I can’t say I’m really surprised, as I’ve been trying to get my hands on such a laptop since the HP Envy 14 launched. If it worked perfectly and could match NVIDIA’s Optimus, I imagine AMD and/or their partners would have been pushing it into reviewers’ hands a lot more. Regardless of delays in getting a test sample, we’ve finally had a chance to test AMD’s Dynamic Switchable Graphics and we can tell you where it stands…sort of. Let’s recap.
AMD’s dynamic switching is fine when it works, but in our testing it fails to work on a regular basis. Mostly, it just feels like it needs more development and testing; given sufficient resources and time all of the issues I’ve experienced on the VAIO C could get resolved. Long-term, AMD needs a lot more games to get explicit support; out of sixteen titles, not even counting OpenGL games, four of the games had some sort of problem with dynamic switching. On an NVIDIA Optimus laptop, every single game worked without any tweaking necessary. That’s what AMD needs to achieve at this point, and preferably do so without any performance compromises.
The bigger issue of course is that AMD needs to get their laptop partners—Sony in this case—to release regular driver updates, and to use up-to-date driver builds when laptops launch. For all we know many of the issues have been addressed in the months since the February build; instead, Sony has a driver released in June 2011, but with a version number that suggests it was already over four months old at the time the VAIO VPCCA290X launched. We found that the Llano A8-3500M with the HD 6630M outperformed the VAIO CA, which simply shouldn’t happen (unless AMD has some special optimization on Llano that allow their GPUs to run faster). It looks like Sony has given up at least 10% of the performance potential of HD 6630M on average, and in some games the outdated drivers may be culling a third of the performance potential.
That’s really my main concern if you haven’t noticed: drivers. If you have an AMD IGP and AMD GPU (e.g. Llano), some of this discussion becomes unnecessary. Since AMD provides both graphics drivers in that case, updates should be a lot easier, although OEMs would still need to sanction the reference drivers. If an OEM were willing to commit the resources necessary to at least do bi-monthly driver updates for switchable graphics, that would also be sufficient, but they’d need a proven track record of doing so—something no laptop manufacturer has ever achieved. Another alternative is for AMD to get the OEMs on board with letting AMD release reference drivers, including for switchable graphics platforms on Intel chipsets, but no one has managed to do that either and I don’t see things changing. As noted earlier, AMD already has plans in place to move to fully independent graphics drivers, hopefully some time in 2012, but best-case we’re four months away and worst-case it might not even happen in 2012.
That’s another part of the problem with AMD’s drivers, unfortunately: they currently have people working on Brazos, Llano, the upcoming Trinity, existing desktop and notebook graphics, the HD 7000 series, and switchable graphics (plus some other tidbits I missed I’m sure). I doubt that fixing their Dynamic Switchable Graphics drivers will take priority over getting HD 7000 and Trinity drivers ready, and AMD could probably use more people working on improved compiler support for Bulldozer while we’re at it. In other words, there are a lot of areas in AMD software development that need people, and how many people are working on Dynamic Switchable Graphics is unknown. NVIDIA’s Optimus Technology currently enjoys a healthy lead in dynamic switchable graphics and AMD is trying to play catch up, and I’m not sure they’re ready to commit the manpower required to make it happen. It’s hardly a surprise then that where more than 100 Optimus enabled laptops have launched in the past 18 months, there are only a few laptops with AMD’s Dynamic Switchable Graphics—and only a dozen or so laptops using any form of AMD switchable graphics to my knowledge.
To be fair, let me also point out that NVIDIA's Optimus Technology didn't launch and immediately work with everything. Taken from that perspective, AMD's Dynamic Switchable Graphics is about 18 months behind NVIDIA, and hopefully we'll see the technology mature and improve during the next year. We look forward to the day where the compatibility problems we experienced are largely addressed, and we can all get back to using our computers rather than wrestling with them. (Wake me when that happens!) AMD has the groundwork laid at least, so whether it takes six months or 18 months, at some point we should have the ability to get updated drivers for our AMD, Intel, and NVIDIA graphics solutions without worrying about breaking certain features. If that sounds like a pipe dream, just ask some of us old timers about the joys of DOS drivers, loading high, and EMM386.SYS.
As far as the VAIO CA goes, Sony makes a decent laptop—we’ll give it a separate review shortly. The VAIO CA isn’t at quite the same level in terms of build quality and materials as the VAIO SB Dustin reviewed, but it does provide reasonable performance and some of the best battery life results we’ve seen for the specs. If nothing else, Sony at least knows how to tune their laptops for long battery life. Pricing is where things get dicey; there are some $800 VAIO C models that have the same specs as the review unit, but it’s not clear if they include the HD 6630M or not—we’re guessing not. Going straight to Sony, you can configure the VPCCA290X with all the options of our review unit at a not-too-onerous price of $930. Where Sony completely fails however is in their driver support; shipping a laptop with discrete graphics using drivers that are at least four months old (at the time of launch) is tantamount to telling your customers that they don’t need the graphics card at all! But we say the same thing about HD 6470M and yet several companies (including Sony) are still using it.
Ironically, I’d rather have something like the HP Envy 14 or the Sony VAIO C without AMD’s switchable graphics and just give me a discrete GPU instead; that would make getting updated video drivers easier and battery life doesn’t even suffer all that much. AMD is actually a bit closer to my ideal of not needing switchable graphics than NVIDIA, as their mainstream GPUs tend to use less power. Their HD 6630M still draws about 2.0~2.3W more than Intel’s HD 3000 IGP under low loads and 2.8W more during H.264 decoding, but that compares to around 4.3W more for a GT 540M doing H.264 decoding. (We can’t test idle power draw since Optimus just shuts the dGPU off—not that that’s a bad thing.) Of course, the 6630M at ~8.3W idle is still using about 30% more total power than with the IGP (6.0W), but you can still get over six hours of battery life.
Given the price of $930 for the Sony VAIO C, at that point you’re within $150 of better built laptops with nice 1080p displays—e.g. the Dell XPS 15z, or wait for the XPS 14z to show up and see what it offers. If you don’t mind the CPU throttling (or at least running games while using ThrottleStop), you can also grab the Acer TimelineX 3830TG-6431 we used as a comparison point in this article for just $700. The MSI X460DX-008US for $727 (with i3-2310M and a 14” LCD), 15.6” Acer Aspire AS5750G-6496 for $680, or the 15.6” Gigabyte Q2532N-CF1 for $885 are also available for less money than the Sony—and that’s just naming a few of the Optimus laptops with Sandy Bridge CPUs and GeForce GT 540M GPUs. In short, you can get any laptop equipped with NVIDIA’s Optimus Technology and get the improved battery life that running off the IGP affords while still having readily available driver updates, frequently at a lower price. Unless you absolutely don’t care about driver updates—or a UI with lack of “expert” features like a list of game and application profiles and global settings—NVIDIA is definitely the way to go for dynamic switchable graphics technologies right now.
Just to wrap things up, obviously I’m just one person testing these things out, and we have a lot of readers. It’s also been frustrating trying to get a laptop with AMD Switchable Graphics in for testing, and while NVIDIA shipped us a Sony VAIO C, it’s possible that other laptops out there (HP dv6/dv7 and Envy 15/17) might have better driver support. Hopefully we’ll be able to get one (or more) of those for testing, at which time we can revisit this subject, but until then I’d love to hear your thoughts and input on switchable graphics as well as compatibility. What problems/glitches have you run into with Optimus that I might have missed? Outside of Linux non-support, are there any major issues with Optimus that you’d like addressed? The same goes for the AMD side: what other titles are having issues on any of the dynamic switchable graphics laptops? How have laptops with AMD switchable graphics fared in terms of driver updates over time? Does AMD’s switchable technology work any better under Linux that NVIDIA’s Optimus? If any of you can provide specific complaints/concerns with details of how to reproduce the problem(s) for either platform, please sound off in the comments section, or shoot me an email.