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AMD A10-7800 APU Review: Kaveri Hits the Efficiency Sweet Spot

Results: CPU

For many years, I was the lead programmer for custom business sector-specific applications, and in lieu of synthetic benchmarks, which may not be relevant to real-world applications, I created three tests using software from that world.

One Thread Solving a Complex Problem

The first program optimizes building a complex brick wall. A 60-foot-long stretch contains eight windows and two door openings, including the frames and jambs. Small holes for the spools of horizontal blinds and three interlocking walls also have to be placed. The goals are minimizing the number of split bricks and optimizing re-use of split bricks so that waste is almost eliminated. Since placement of bricks depends on where other bricks are located, the task can't be parallelized easily. So, it runs in a single thread, while memory use is negligible.

Intel's Core i3 wins this benchmark comfortably, delivering performance that's 20% faster than AMD's A10-7850K. However, since we are only talking about a three-second run time, the absolute difference isn't significant. Then again, we've seen similar scaling in our single-threaded iTunes and LAME benchmarks, too.

4 Threads = 4 Jobs?

The next application optimizes solar panel placement by considering the sun's position throughout the day, each of the 365 days in a year, from sunrise to sunset, in one-hour intervals. Two trees, a neighbor’s house, and a few chimneys create shadows, and in some light conditions, front-row solar panels throw shadows on second-row panels as well. This program also optimizes the placement of wiring. Furthermore, based on historical meteorological data, the expected energy output for the whole year is estimated. This software can be easily parallelized, as the energy output corresponding to each sun position is calculated independently.

While the Core i3-4330 is still in front, it’s a closer race since Hyper-Threading technology doesn't quite match the effectiveness of four integer units. The Haswell-based Intel CPU is barely faster than the A10-7850K, while beating the lower-clocked A10-7800 by 6%. The older Core i3-2100, which we included for comparison purposes, clearly shows its age.

We further increase the degree of parallelization by running a photo-realistic renderer on several computers on a network. For instance, all of a company's office PCs can be harnessed for a computation-intensive task like rendering. One PC serves as the controller, which farms out jobs to other PCs based on their hardware capabilities. In this test, each of the compute clients runs four worker threads.

The different CPU and APU models are even closer together due to communication overhead and increased memory footprint. The A10-7850K manages a win against the Core i3-4330, and the A10-7800 finishes a close third. What do we learn from this benchmark? Real-world applications involve more moving parts than video transcoding or gaming. While IPC is naturally an important consideration, it's not all-telling.

A Typical Consumer Application: Video Compression

When an application doesn't support OpenCL, or OpenCL acceleration is disabled, the Kaveri architecture's two modules address up to four threads in parallel. We decided to use HandBrake as a benchmark to test this. As expected, the A10-7800 winds up in the middle of our test field.

  • blackmagnum
    Just to wonder if Microsoft or Sony were to put this chip in their next gaming consoles and give those gamers a fighting chance.
    Reply
  • tiger15
    You are stressing power efficiency.
    What about comparing those numbers with other offerings? (Intel?)
    Reply
  • Memnarchon
    13989815 said:
    Just to wonder if Microsoft or Sony were to put this chip in their next gaming consoles and give those gamers a fighting chance.

    Maybe the new consoles lack CPU power (even if they are 8 core, the 1,6Ghz/1,75Ghz cripples them), their GPU part is far more powerful than existing APUs.
    PS4's GPU has cores like 7870 and XBOX1 has cores like 7790, in other words more powerful than the 512 core R7 which exists in today's best APU A10-7850K.
    Reply
  • damric
    Why is this so late to market?
    Reply
  • Cryio
    Wait. You can now CrossFire A10 7850 with GPUs other than the 240 and 250X?

    I have a friend with a 7850K and a 260X and he's dying to know if he can CrossFire.

    "I see no point in buying a processor that emphasizes on-die graphics and then adding a Radeon R7 265X. Yes, AMD officially recommends it and yes, we tried it out." Can I take this as a yes ?
    Reply
  • gadgety
    The A8-7600 seems to be the effiency sweet spot in the Kaveri line up, specially at 45W. Trying to compare with of the A10-7800 with the A8-7600, although as far as I can tell just about ALL your tests seem to be done at different settings (e.g. BioShock Infinity is run at Medium Quality Presets rather than the lowest settings as in the test of the A10-7800) so the comparison isn't straightforward. A8-7600 is within 91-94% of the A10-7850K. One item which is comparable is video encoding in Handbrake, where the A8-7600 is at 92.8% of the 7850k, whereas the A10-7800 is at 95.7% of the 7850k. Price wise you'd pay a 63% premium for the A10-7800 over the A8-7600 to get an extremely minute performance advantage, around 3% or so.
    Reply
  • Drejeck
    13989815 said:
    Just to wonder if Microsoft or Sony were to put this chip in their next gaming consoles and give those gamers a fighting chance.

    Maybe the new consoles lack CPU power (even if they are 8 core, the 1,6Ghz/1,75Ghz cripples them), their GPU part is far more powerful than existing APUs.
    PS4's GPU has cores like 7870 and XBOX1 has cores like 7790, in other words more powerful than the 512 core R7 which exists in today's best APU A10-7850K.
    Not accurate.
    PS4 GPU is a crippled and downclocked 7850 (disabled cores enhance redundancy and less dead chips)
    XB1 GPU is a crippled and downclocked R7 260X (as above) and like the 7790 should have AMD True Audio onboard, but they could have changed that. This actually means that CPU intensive and low resolution games are going to suck because the 8 cores are just Jaguar netbook processors.
    The reality is that PS4 is almost cpu limited already and the XB1 is more balanced. Now that we've finished speaking of "sufficient" platforms let's talk about the fact that a CPU from AMD and the word efficient are in the same phrase.
    Reply
  • Memnarchon
    13990605 said:
    Not accurate.
    PS4 GPU is a crippled and downclocked 7850 (disabled cores enhance redundancy and less dead chips)
    I think you need to do a little more research since: Reverse engineered PS4 APU reveals the console’s real CPU and GPU specs. "Die size on the chip is 328 mm sq, and the GPU actually contains 20 compute units — not the 18 that are specified. This is likely a yield-boosting measure, but it also means AMD implemented a full HD 7870 in silicon."
    13990605 said:
    XB1 GPU is a crippled and downclocked R7 260X (as above) and like the 7790 should have AMD True Audio onboard, but they could have changed that. This actually means that CPU intensive and low resolution games are going to suck because the 8 cores are just Jaguar netbook processors.
    The reality is that PS4 is almost cpu limited already and the XB1 is more balanced. Now that we've finished speaking of "sufficient" platforms let's talk about the fact that a CPU from AMD and the word efficient are in the same phrase.

    The PS4 will be CPU limited? Since they write the code/API according to a hardware that it will remain the same for like 7-8 years, such thing as CPU limited especially for a console that runs the majority of games at 1080p, does not exist...
    ps: I agree with the downclocked part since they need to save as much power as they can...
    Reply
  • blubbey
    13989815 said:
    Just to wonder if Microsoft or Sony were to put this chip in their next gaming consoles and give those gamers a fighting chance.

    Maybe the new consoles lack CPU power (even if they are 8 core, the 1,6Ghz/1,75Ghz cripples them), their GPU part is far more powerful than existing APUs.
    PS4's GPU has cores like 7870 and XBOX1 has cores like 7790, in other words more powerful than the 512 core R7 which exists in today's best APU A10-7850K.
    Not accurate.
    PS4 GPU is a crippled and downclocked 7850 (disabled cores enhance redundancy and less dead chips)
    XB1 GPU is a crippled and downclocked R7 260X (as above) and like the 7790 should have AMD True Audio onboard, but they could have changed that. This actually means that CPU intensive and low resolution games are going to suck because the 8 cores are just Jaguar netbook processors.
    The reality is that PS4 is almost cpu limited already and the XB1 is more balanced. Now that we've finished speaking of "sufficient" platforms let's talk about the fact that a CPU from AMD and the word efficient are in the same phrase.

    PS4 is 1152:72:32 at 800MHz, 7850 is 1024:64:32@ 900MHz or so (860MHz release?) It is not a "crippled 7850", the 7850 is a crippled pitcairn (20 CUs is the full fat 7870, PS4 has 18, 7850 16 CUs). "CPU limited" is very PC orientated thinking, things like offloading compute to the GPU will help. No, I'm not saying their CPUs are "good" but they will find ways of offloading that work onto the GPU.
    Reply
  • silverblue
    The A8-7600 seems to be the effiency sweet spot in the Kaveri line up, specially at 45W. Trying to compare with of the A10-7800 with the A8-7600, although as far as I can tell just about ALL your tests seem to be done at different settings (e.g. BioShock Infinity is run at Medium Quality Presets rather than the lowest settings as in the test of the A10-7800) so the comparison isn't straightforward. A8-7600 is within 91-94% of the A10-7850K. One item which is comparable is video encoding in Handbrake, where the A8-7600 is at 92.8% of the 7850k, whereas the A10-7800 is at 95.7% of the 7850k. Price wise you'd pay a 63% premium for the A10-7800 over the A8-7600 to get an extremely minute performance advantage, around 3% or so.

    Yes, but the A8-7600 has a 384-shader GPU. I suppose it depends on whether you want to use the GPU or not.
    Reply