Earlier this month we previewed AMD's Llano architecture in a notebook environment. Now we have the desktop version with a 100 W TDP. How much additional performance can the company procure with a loftier thermal ceiling and higher clocks?
Editor's Note: As we've done so many times before, we're partnering up with CyberPower to give away one of the first Llano-based desktop machines, which the builder calls its Gamer Ultra, to one of our readers. Flip through our review and, on the last page, enter to win a brand new PC, compliments of CyberPower!
A8-3850 Makes Its Desktop Debut
Don Woligroski did an absolutely killer job on our first look at AMD’s Llano architecture. If you haven’t yet read that story and you want to know more about the plumbing inside the company’s first mainstream APU, you really owe it to yourself to check out The AMD A8-3500M APU Review: Llano Is Unleashed before diving into this piece.
Because Don covered the underlying architecture so well, I’m going to use our first experiences with AMD’s Llano-based desktop platform, code-named Lynx, to dive deeper into the stuff I know you guys love: benchmark results and analysis. What kind of performance can you expect out of Dual Graphics? How does Sandy Bridge with discrete graphics compare? What effect does memory performance have on gaming frame rates? How does integrated USB 3.0 support measure up to some of the add-on controllers we’ve seen? I’ll answer all of that.
But first let’s go over the basics of AMD’s first desktop-class Llano-based APUs.
Llano: The Recession-Friendly APU
Oh, Audi would be so proud (or maybe not, given the entry-level pedigree of these processors). AMD is using the same A8 and A6 designators to distinguish between the perceived performance levels of its four launch SKUs.
There are two A8s and two A6s. The Llano-based flagship is A8-3850, a 100 W part with Radeon HD 6550D graphics, four execution cores with 1 MB L2 cache each, and a 2.9 GHz clock rate. That part does not offer Turbo Core support—the only way to get it running faster than 2.9 GHz is through overclocking. AMD says to expect pricing around $135.
The A6-3650 is also rated at 100 W, even though it’s armed with Radeon HD 6530D graphics and a more conservative 2.6 GHz clock rate (again, Turbo Core isn’t available). The -3650 boasts four cores as well, includes the same 4 MB of L2 cache, and support DDR3-1866 data rates, just like the other three models. That one is expected to run $115.
| Model | GPU | TDP | Cores | Base CPU Clock | Max. Turbo | L2 Cache | Shaders | GPU Clock | Turbo Core |
|---|---|---|---|---|---|---|---|---|---|
| A8-3850 | HD 6550D | 100 W | 4 | 2.9 GHz | - | 4 MB | 400 | 600 MHz | No |
| A8-3800 | HD 6550D | 65 W | 4 | 2.4 GHz | 2.7 GHz | 4 MB | 400 | 600 MHz | Yes |
| A6-3650 | HD 6530D | 100 W | 4 | 2.6 GHz | - | 4 MB | 320 | 443 MHz | No |
| A6-3600 | HD 6530D | 65 W | 4 | 2.1 GHz | 2.4 GHz | 4 MB | 320 | 443 MHz | Yes |
Interestingly, dipping down to the 65 W level doesn’t seem to sacrifice much in the way of functionality. AMD’s A8-3800 includes the capable Radeon HD 6550D engine, quad-core Stars architecture, and 4 MB L2 repository. However, Turbo Core helps compensate for a fairly severe drop to 2.4 GHz, kicking frequency up to 2.7 GHz in situations where thermal headroom allows for it. Unfortunately, AMD didn’t send over any Turbo Core-equipped processors for testing, so it’s impossible to gauge how much time this four-core part spends at its elevated setting.
Finally, the A6-3600 is also a 65 W component. It scales way back, though, giving up not only processor clock rate—its four cores running at 2.1 GHz by default and up to 2.4 GHz with Turbo Core—but also graphics performance via the less-complex Radeon HD 6530D engine. Is still includes 4 MB of L2 cache though, complementing each core with 1 MB.
What's the difference, exactly, between the Radeon HD 6550D and Radeon HD 6530D GPU engines? One SIMD engine, for the most part.
| Graphics Processor Classification | Radeon HD 6550D (A8-Series APUs) | Radeon HD 6530D (A6-Series APUs) |
|---|---|---|
| Shader Cores | 400 | 320 |
| SIMDs | 5 | 4 |
| Texture Units | 20 | 16 |
| Render Back-Ends | 2 | 2 |
| Z/Stencil ROPs | 32 | 32 |
| Color ROPs | 8 | 8 |
| GPU Clock Rate | 600 MHz | 443 MHz |
| Peak Compute Power | 480 GFLOPS | 284 GFLOPS |
When you look at a block diagram of the Llano's GPU component, it's easy to see how AMD differentiates these two lineups. Each SIMD hosts 80 ALUs and is associated with four texture units. Turning one SIMD off yields the 320 shaders and 16 texture units offered by Radeon HD 6530D.
A Small Launch Gets Smaller
With four SKUs in the initial Llano-based desktop portfolio, a zero-hour revelation that the 65 W A8-3800 and A6-3600 won't be available until an undisclosed date narrows the family down to two models: A8-3850 and A6-3650, both 100 W parts. As a result, it won't be possible to test Turbo Core functionality on Llano until AMD addresses the availability of its lower-power offerings.
- Meet AMD’s Desktop Llano-Based Lineup
- Dual Graphics: How Does It Perform?
- Dual Graphics: Not Always Your Best Bet
- Chipsets
- Storage Performance
- Making Memory Performance Matter Again
- A Word On Overclocking Llano
- Test Setup And Benchmarks
- Benchmark Results: PCMark 7
- Benchmark Results: 3DMark Vantage
- Benchmark Results: Sandra 2011
- Benchmark Results: Metro 2033 (DirectX 10)
- Benchmark Results: Call of Duty: Modern Warfare 2 (DirectX 9)
- Benchmark Results: World Of Warcraft: Cataclysm (DirectX 9 And 11)
- Benchmark Results: Content Creation
- Benchmark Results: Productivity
- Benchmark Results: Media Encoding
- Power Consumption
- Conclusion



Actually Llano on the Desktop is (IMO) aimed at HTPC a 100% and, off course, notebooks.
I would really, really like to see more media features with the Llano parts you guys have if it can be done 8)
Great article as usual!
Cheers!
No shit, really? I wouldn't have thought so, it's just twice the price!
Great review Chris. For the target market AMD is doing a pretty good job here with an old CPU architecture and once they pair this with Bulldozer they should have a killer product.
They don't want you to see better performance from a cheaper APU in single-threaded apps by pushing Turbo Core further ;-)
So is AM3+ going to be retired in favor of FM1 in the near future? Why are there chipset at all? Why isn't everything SOC by now?
Otherwise this is a very good CPU. If AMD has used 1 MB level 2 caches in their quads when they came out with the Deneb Propus die, they would be much more competitive.
what about power consumption?
That's about all the sense it makes then, for mobile and all-in-one units, but for cheap desktops... eh.
Actually Llano on the Desktop is (IMO) aimed at HTPC a 100% and, off course, notebooks.
I would really, really like to see more media features with the Llano parts you guys have if it can be done 8)
Great article as usual!
Cheers!
And I think you guys may have gotten the min and avg FPS scores for the CoD:MW benchmark backwards... How can the min be higher than the average? Maybe you were actually comparing No AA to 4x AA or something, not min and avg FPS?
600Mhz to 840/900Mhz? No problem at all.
Anyway, The real show should be bulldozer-based APU's. If they could just get the graphics up to a 5750 level...
As for a higher end desktop, I am waiting for BD and how it affects the market. That will determine which parts I keep and which parts get put into an HTPC.