Original Link: http://www.anandtech.com/show/4023/the-brazos-performance-preview-amd-e350-benchmarked
The Brazos Performance Preview: AMD E-350 Benchmarkedby Anand Lal Shimpi on November 16, 2010 12:01 AM EST
Update: Be sure to read our full review of AMD's E-350 here.
Last week I mentioned that I had recently spent some time with AMD down in Austin, TX, benchmarking its upcoming Brazos platform. The Brazos platform is composed of an AMD Zacate or Ontario APU and the Fusion Controller Hub (a South Bridge based on the SB800 series). Brazos systems will run the gamut of mainstream notebook, netbook and nettop segments ranging from $299 to around $500. While AMD let us reveal the fact that we tested Brazos, we weren't allowed to publish numbers last week. Today, we can.
I didn’t have much time with Brazos. The AMD briefing started at 9AM, but AMD wanted to go through some marketing slides and answer questions before letting us at Brazos. Going into this whole thing I was worried that I wouldn’t have enough time to run everything I wanted to run. You see, the system I had access to wasn’t pre-configured. It had Windows 7 x64 loaded on it, drivers installed and PCMark Vantage - but everything else was up to me. Despite having a 128GB Crucial RealSSD C300, installing a dozen applications and games still took hours on the system. I asked AMD if I could at least begin copying/installing some applications before we started the briefing, they gladly entertained my request.
I brought an SSD full of applications, games and benchmarks that I wanted to run on the Brazos platform. I purposefully avoided any large test suites (PCMark Vantage, SYSMark) because they would eat up a lot of time and I had no idea how long the rest of the benchmarking would take.
The Brazos test platform
I also didn’t run any of our media streaming suite. The Zacate/Ontario APUs feature AMD’s UVD3 engine and should, in theory, have similar media playback features to the Radeon HD 6000 series. Of course once we have final systems it’ll be easier to put this to the test. I was mainly interested in characterizing the CPU and GPU performance of Brazos, the two major unknowns.
I didn’t get into the full swing of testing until just before 11AM, and we had a hard stop at 5PM. That didn’t leave a ton of time, but I believe it left enough to get a good idea for what Brazos will perform like in the real world.
As I mentioned in Part 1 of our coverage, the system felt snappy. I had the 11-inch MacBook Air on hand (it served as my Excel-runner while I benchmarked) and interacting with the OS felt no different between the Brazos system and the 1.6GHz MBA. That being said, the MBA is technically much quicker (and more expensive).
|AMD Brazos Lineup|
|APU Model||Number of Bobcat Cores||CPU Clock Speed||GPU||Number of GPU Cores||GPU Clock Speed||TDP|
|AMD E-350||2||1.6GHz||Radeon HD 6310||80||500MHz||18W|
|AMD E-240||1||1.5GHz||Radeon HD 6310||80||500MHz||18W|
|AMD C-50||2||1.0GHz||Radeon HD 6250||80||280MHz||9W|
|AMD C-30||1||1.2GHz||Radeon HD 6250||80||280MHz||9W|
The system I tested had AMD’s E-350 processor, the highest end APU you’ll find on a Brazos. This is the chip you’ll find in $400 nettops and notebooks in the $400 - $500 range. This puts its direct competition as really expensive Atom based netbooks, Pentium dual-core notebooks and low end Core i3 notebooks. While the latter two should easily outperform the E-350 in CPU intensive tasks, the GPU comparison is another story entirely. It’s also worth noting that the E-350 carries an 18W TDP (including graphics). During my testing I measured a maximum total system power consumption of around 30W (including the 1366 x 768 LCD panel) while playing games and around 25W while encoding H.264 on the two Bobcat cores. The system idled around 15W however AMD cautioned me that this number was unnaturally high. Final Brazos systems will be far more power optimized and AMD expects numbers to drop down to as low as 5.6W.
AMD is confident we will see Brazos based systems deliver well beyond 6 hours of battery life. AMD's goal is to deliver Atom like battery life and form factors, with a real GPU and hopefully better than Atom performance. We spent our time in Austin trying to find out if its goals were realistic.
Setting Performance Expectations
AMD provided this slide of PCMark Vantage and 3DMark Vantage performance of Brazos compared to its existing mobile platforms (Danube and Nile):
If you look at the PCMark Vantage numbers you'll see that AMD's E-350 provides roughly the same performance as an Athlon V120. That's a single core, 45nm chip running at 2.2GHz with a 512KB L2 cache. Or compared to a dual core processor, it's within striking distance of the Athlon Neo K325 which features two cores running at 1.3GHz and 1MB L2 per core. The GPU performance however tells a very important story. While AMD's previous platforms offered a great deal of CPU performance and an arguably imbalanced amount of GPU performance, Brazos almost does the opposite. You get a slower CPU than most existing mainstream platforms, but a much better GPU.
In the sub-$500 market, you're not going to get much in the way of a discrete GPU. What AMD is hoping for is that you'll be happy enough with Brazos' CPU performance and be sold on its GPU performance and total power consumption. From AMD's standpoint, there's not much expense involved in producing a Zacate/Ontario APU, making Brazos a nice way of capitalizing on mainstream platforms. The 75mm2 die itself is smaller than most discrete GPUs as well as anything Intel is selling into these market segments.
AMD's Zacate APU, 19mm x 19mm package, 413 balls, 75mm^2 die
Brazos, like Atom, will fight a two front war. On the one hand you have the price comparison. The E-350 will be found in notebooks in the $400 - $500 range according to AMD. That puts it up against mainstream notebooks with 2.2GHz Intel Pentium DC and 2.26GHz Core i3-350M processors. Against these platforms, Brazos won't stand a chance as far as CPU performance goes but it should do very well in GPU bound games. I've included results from a 2.2GHz Pentium dual-core part (1MB L2 cache) as well as a simulated Core i3-350M in the mobile IGP comparison.
The other front is, of course, the ultraportable space. Here you'll see the E-350 go head to head with dual-core Atom, Core 2 ULV and Arrandale ULV parts. AMD's CPU performance should be much more competitive here. From this camp we've got the Atom D510 (close enough to the N550) and a simulated Core i3-330UM. The expectations here are better CPU performance than Atom, but lower than Arrandale ULV. GPU performance should easily trump both.
Memory and Cache Latencies
The Brazos platform was configured with 4GB of DDR3-1066 memory. The IDF system had memory running at DDR3-1333, however AMD had to decrease clocks presumably to meet validation requirements for final silicon. I measured an 86.9ns trip to main memory, a 3 cycle L1 and a ~22 cycle L2 cache. That's a lower latency memory interface than Atom or Core 2 based processors, but a higher latency L2.
CPU Performance: Better than Atom, 90% of K8 but Slower than Pentium DC
AMD's performance target for Bobcat was 90% of the performance of K8 at the same clock speed and our Photoshop CS4 benchmark shows that AMD can definitely say that it has met that goal. At 1.6GHz the E-350 manages to outperform a pair of K8s running at 1.5GHz in the Athlon X2 3250e. Unfortunately for AMD, Intel's Pentium dual-core running at 2.2GHz is much quicker. Most notebooks in the $400+ range have at least a 2.2GHz Pentium. Even the Atom D510 isn't far behind.
AMD tells me that in general purpose integer tasks, the E-350 should do well and it may even exceed AMD's 90% design target. However in higher IPC workloads, for example many floating point workloads, the E-350 is constrained by its dual issue front end. In these situations, the out of order engine is starved for instructions and much of Bobcat's advantage goes away.
Our x264 HD test has the E-350 performing within 86 - 92% of the Athlon X2 3250e, once again meeting AMD's design targets. Unfortunately, this isn't much faster than an Atom - mostly thanks to Atom's Hyper Threading support. Although not an out of order architecture, Atom gets a healthy efficiency boost by being able to execute instructions from two threads per core. Once again, compared to a 2.2GHz Pentium, the E-350 isn't close. Even VIA's dual core Nano is faster. When it comes to power consumption however, the E-350 can't be touched. I measured max system power consumption at 25.2W while running the x264 encode test. With the exception of the Atom D510, the rest of the desktop platforms here consume much more than that at idle (much less under load).
Despite being a offline 3D rendering benchmark, our 3dsmax 9 test does fall in line with expectations. The E-350 delivers 92% of the performance of the Athlon X2 3250e and outperforms the Atom D510 by 26%. Unfortunately for AMD, the Pentium dual-core holds onto a significant performance advantage here. Clock for clock, Bobcat won't be able to do much against anything Core 2 based. The real advantage here will be GPU performance.
Single Threaded Performance
In most of our benchmarks the performance advantage over Atom isn't huge, yet using Brazos is much better than using an Atom based machine. It all boils down to one thing: single threaded performance. Atom can make up for its deficiencies by executing a lot of threads in parallel, but when you're bound by the performance of a single thread the E-350 shines. The E-350 is 65% faster than the Atom D510 in the single threaded Cinebench R10 test. It's this performance advantage that makes the E-350 feel so much quicker than Atom.
The Core i3-330UM manages a 46% performance advantage over the E-350. Even in the ultraportable Arrandale ULV space at lower clocks, AMD still leaves a lot of CPU performance on the table. The advantage here will be cost. A single E-350 is less than 40% of the die area of a Core i3-330UM. You may not get the same CPU performance, but performance per mm^2 is much higher.
In the multithreaded Cinebench test Atom is able to catch up quite a bit, but the E-350 still holds an 11% advantage.
File Compression/Archive Recovery Performance
Our final two CPU tests are both multithreaded and they show the E-350 equaling and falling behind the performance of the 1.5GHz Athlon X2. As we explained earlier, the gap between the E-350 and Atom shrinks as you add more threads to the workload.
Desktop IGP Comparison: Faster than Clarkdale
I split the graphics comparison into two sections: desktop and mobile. For the desktop section I compared the E-350 to the latest Clarkdale chips, AMD's own 890GX and a discrete Radeon HD 5450 graphics card. While the Radeon HD 5450 has the same number of shader processors as the E-350 (80), they run faster and it has a dedicated 1.6GHz memory bus to feed it. The E-350 has to share memory bandwidth between the two Bobcat cores and the 80 SPs, severely limiting its performance potential.
The E-350 does extremely well compared to its desktop brethren. In our Modern Warfare 2 and BioShock tests its easily faster than the Core i3/i5 and in the case of BioShock 2 it's even faster than AMD's 890GX. Dragon Age Origins is another story however as the benchmark is primarily CPU limited, giving the desktop parts a huge advantage. In GPU bound scenarios, it's clear that our initial Zacate benchmarking was accurate: the E-350's Radeon HD 6310 is quicker than Intel's HD Graphics.
Compared to the Radeon HD 5450 the 6310 offers between 66 - 69% of its performance in our GPU bound tests. The performance reduction is entirely due to the 6310's limited memory bandwidth being shared with the dual Bobcat cores on-die.
Mobile IGP Comparison
I narrowed down the platforms for our mobile IGP comparison. I simulated a Core i3 350M by taking an i3-530, underclocking it (I couldn't do anything about the 4MB vs. 3MB L3 cache) and capping its GPU frequency at 667MHz. This is the best case scenario for the i3-350M, and as you'll see below, it doesn't really matter. I also paired a 2.2GHz Pentium Dual-Core with a G45 motherboard, agian simulating the cheaper mobile Pentium platform. Finally I installed Windows 7 on the 1.6GHz Core 2 Duo based 11-inch MacBook Air with its GeForce 320M to give you an idea of the upper bound for mobile performance with what might as well be a low end discrete GPU.
Updated: I've added performance results from a simulated Core i3-330UM, the E-350's competition in ultra portables.
We'll start with Modern Warfare 2:
The E-350 puts the i3-350M, i3-330UM and Pentium DC to shame, delivering 67% better performance. The frame rate is just shy of being totally smooth however. I found that in most modern games 1024 x 768 would result in frame rates just under 30 fps.
BioShock 2 showed a similar performance advantage. Again we're not able to break 30 fps but the performance advantage is huge compared to the Intel platforms with integrated graphics.
Dragon Age: Origins is mostly CPU bound at low quality settings and thus there's no real advantage to the E-350's Radeon HD 6310 GPU. It's faster than the Pentium/G45 platform, but significantly slower than the i3-350M. I expect most games however to be GPU bound at these settings across the board.
World of Warcraft continued the trend. The E-350 ended up 57% faster than the i3-350M, although still fell short of a discrete GPU.
Of course I wondered how well Brazos would play Starcraft 2:
The GPU handles SC2 just fine, however the game is very CPU dependent and thus you see a pretty big advantage from the mainstream i3 system. The comparison is a lot closer when we look at the i3-330UM. The E-350 won't be able to play SC2 as well as a $500 mainstream notebook, but it'll be comparable to an ultraportable running ULV Arrandale.
We don't have numbers for the G45 platform here because the system wouldn't run our benchmark (our tests use an older version of SC2 which apparently had issues with the G45 drivers).
Our SC2 CPU test gives you an idea of the lower end of performance in large multiplayer battles:
The E-350 offers only 58% of the performance of the i3-350M system. The Bobcat cores do hold the platform back from time to time. Again, compared to the i3-330UM there's no performance difference at all.
Just for kicks I also ran the Civilization V benchmark, which gave us two datapoints: GPU performance and no-render/CPU performance.
The benchmark doesn't score well on either platform, although AMD does hold a 72% performance advantage over the i3 and G45 platforms. The CPU test puts the E-350 at about 55% of the speed of the Pentium dual core platform.
Civ V is one area where the Arrandale CPU advantage wins out over GPU performance.
Overall, the E-350 has no problems outperforming any of the current Intel integrated graphics offerings in 3D games. In CPU bound titles the E-350 loses out to the mainstream i3, but is competitive with ultra low voltage i3s. Just as with Atom, you'll have to sacrifice performance vs. a mainstream notebook, but compared to low voltage Arrandale the E-350 can hold its own.
The Brazos platform really poses the question of what is fast enough from a CPU standpoint. Netbook makers often argued that Atom was fast enough, and honestly they'd be right if Atom wasn't paired with such a heavyweight OS. Running Windows 7, Atom just wasn't fast enough but many made the sacrifice in order to get the form factor and battery life benefits that went along with the platform. The E-350 offers an alternative. You get faster than Atom CPU performance (particularly in single threaded tasks) and a fairly potent GPU. The only issue is that the E-350 doesn't compete against Atom. Most of the time you'll find it up against Pentium or low end Core i3 notebooks.
From a CPU performance standpoint, the E-350 can't compete with either of those CPUs clock for clock. Where AMD has the advantage is in power consumption and GPU performance. This is effectively AMD's answer to Intel's CULV platform, but with better graphics performance.
This is a huge statement from AMD, echoing what Apple has been saying for the past year: while CPU performance matters, GPU performance must scale at least as quickly, if not more to make up for lost time. The only thing we're really lacking are the killer apps (outside of 3D gaming and HD video) to support this mentality today.
The Radeon HD 6310 in the E-350 does very well, despite the memory bandwidth limitations. Its easily faster than Intel's HD Graphics, although some games (e.g. Starcraft 2) are still held back by the performance of AMD's Bobcat cores. Despite being a significant step forward for integrated graphics at this price point, I would be lying if I said I didn't wish it were faster. Ideally I would like to see > 30 fps performance across the board from the E-350.
There's also the GPU compute argument that AMD makes for Fusion, however the GPU compute tests I tried to run on Brazos didn't exactly work. Cyberlink Media Espresso would not use the GPU for encoding and the Civilization V compute shader test wouldn't run either. Both I suspect will be worked out by the time the platform actually ships.
What matters the most with Brazos is what the OEMs do with it. We'll of course get mini-ITX boards to turn into HTPCs, but on the mobile side Brazos needs to be paired with a sleek/well built chassis, good display, fast storage and a large battery to truly be attractive. I am also concerned about the performance of the Ontario based APUs. In many areas the E-350 isn't that much quicker than a dual-core Atom, which makes me wonder how the C-30 and C-50 would do.
Brazos ultimately has the same problem Atom had at its introduction. Compared to similarly priced notebooks based around 2.2GHz Pentium dual-core CPUs or Core i3s, the CPU just isn’t competitive. Unlike Atom however, in GPU bound scenarios the E-350 is actually faster than those two. The only issue, as I mentioned above, is that currently the majority of mainstream applications that are GPU bound are 3D games. Like Atom however, the Brazos platform is also destined for ultra thin formfactors - places a low end Core i3 can’t go. It’s in that comparison that AMD is most successful.
Compared to a Core i3-330UM, Brazos offers much better GPU performance and it’s even competitive in CPU dependent games like Starcraft 2. The i3-330UM is still faster CPU bound scenarios though, reinforcing the CPU speed for GPU performance tradeoff that you’re faced with when considering these two.
The E-350 delivers 50 - 60% of the multithreaded CPU performance of the Core i3-330UM, and nearly 70% of the single threaded performance. It’s a noticeable gap, but AMD attempts to make up for it by delivering up to twice the GPU performance in games.
Then there’s the issue of die size. For years AMD has had to give sell you a larger die at a lower price than Intel in order to remain competitive. The Brazos platform changes that. At 75mm^2, the Zacate die is smaller than just the CPU portion of a Core i3 and it’s less than 40% of the total die area when you include Intel’s HD Graphics. While more CPU performance would be nice to have, this is a good start.
AMD is committed to revving the Brazos platform yearly. We’ll obviously see updated graphics next year but I’m hoping for updates to the CPU cores as well. The biggest mistake Intel made with Atom was to be too conservative with its roadmap. AMD has a history of not making the same mistakes as Intel, so hopefully the Brazos roadmap looks good. Now we wait for the notebooks.