EPIA-M900 power usage and performance

This is the last article from my series about my EPIA-M900 system (first, second). This time I'll focus on power usage numbers, some small performance tests and overall feel.

I used  Tunex multifunction power meter to measure a power usage. All tests were made using Windows 7 64-bit edition. The whole system (including eH1 graphics card and HDD) without monitor uses 44-46W on idle. 44W is more constant than higher values. I tested system on BIOS without graphics card too and it showed 29-31W values. So graphics card adds about 15W on idle. Later I used AIDA64 stress tests and GPU-Z render test to simulate system's maximum power usage with and without HDD stress test. On full load (CPU and GPU) power meter showed 75-77W and 73-74W with and without HDD stress test respectively.  That was the maximum power usage numbers I managed to get on this system. GPU render test raised power usage to 55-56W. CPU load only increased power usage more than GPU load to 68-69W. Finally, while playing Starcraft II this range was between 70-71W. So it is difficult to say how much power usage increased because of GPU or CPU as other components takes some too and overall power usage doesn't increase on the same level as on CPU or GPU load separately.

While power usage numbers are quite good we should look into performance. As of 26 February, 2010 1.6GHz (1.73GHz on turbo) is the maximum frequency you can get from dual core VIA CPUs. VIA Nano X2 L4350E TDP is 27.5W. So you can compare it to low usage mobile CPU (if I am correct, current standard mobile CPU's TDP goes from 25W-45W typically) by TDP. Unfortunately, performance is on the lower range and you need to compare them to Intel Atom and AMD APU from bobcat core series. This is the area where VIA CPU is really competitive. But this article won't make any summary and won't make big comparisons . I will provide only some raw numbers for your investigation and reference. 


Firstly I used y-cruncher multithreaded pi benchmark application. I used 50,000,000 decimal digits test and Linux 0.5.5 Build 9187 version. Total result was 126.278 seconds for this test. Single core VIA Nano L2200@1.6GHz completed test in 299.358 seconds. U2300@997MHz needed 497.043 seconds. The same test was slower on Windows for unknown for me reason (about 20 seconds in total). If you want to compare this result to other CPUs, it is comparable to Intel Celeron T3100 result.

I also ran AIDA64 tests (v2.00.1700). I didn't tested L2200 but AIDA64 had results in their table. Memory read using DDR3-1066 SDRAM 7-7-7-20 CR2 was 3747 MB/s (Nano L2200 with DDR2 3352  MB/s). While memory write test was much faster than L2200, 7138 MB/s against 3157 MB/s. Memory copy 4944 MB/s vs 2759 MB/s. Memory latency was the same 117.3 ns on both systems. CPU Queen - 5890 vs 2580. This test was a little bit faster than AMD E-350 (5169). CPU PhotoWorxx - 5083 vs 2493. For reference Celeron 420 had almost the same result, E-350 had quite lower result at 4375. CPU Zlib - 34.2 MB/s, L2200 - 14.7 MB/s, E-350 31.0 MB/s, Core i5-650 HT - 101.1 MB/s. Padlock module helps VIA Nano CPUs to shine on CPU AES test where L4350E got 86803 points and lost only to CPUs with Intel AES support (though considerably) but others without it lost considerably (even 12xOpteron 2431 got 78761 points), L2200 - 40002 points. CPU Hash test gained 1054MB/s vs 549MB/s (E-350 achieved 326MB/s only). FPU was always quite a weak place for Centaur CPUs but Nano architecture improved FPU performance. FPU V8 436 vs 318, This test was bad for VIA CPUs, even E-350 got a little bit more here. On the hand it showed better results at FPU Julia and Mandel tests 1862vs892 and 832vs428 respectively (E-350 got results in between closer to L2200). Finally FPU SinJulia was a weak place too: 302vs132 while E-350 - 506. This is all tests I made. Tests showed quite mixed results but I believe that L4350 is comparable to first generation dual core AMD K8 CPUs or last generation Pentium 4 CPUs. Somewhere they will be quite faster, elsewhere much slower. They are faster than dual core HT Intel Atom CPUs (at least first generation). The last thing I could test was folding@home project. Unfortunately, this CPU is not suitable for SMP client. It is just to slow (dual core phenom ii@3.2GHz will do 1% 12-15 minutes than this CPU will need 2.5 hours). I also added Windows 7 performance index last time it is here once again (the CPU got minimum 3.9 result):

Windows 7 performance index

In general, it feels that CPU is much slower than Phenom II X2. Active processes like antivirus, flash, program loading grabs quite much from CPU. It is expected result of course. You can't compare apples and oranges this time. However, if you want to feel comfortable at your desktop, this system can be a little to slow. Though it is not that bad after you get into it. I want to change HDD to SSD some day. This should solve slower loading times and I guess should help to feel more responsive and fast while using the system. The only program which used hardware GPU acceleration in videos was Windows Media Explorer (MPC classic unfortunately took only CPU). I will try to investigate this in the future.

I didn't do any GPU tests. I tried to run some DX10/DX11 benchmarks but eH1 was unable to run them at normal FPS. However I played Starcraft II at 1280x1024 without any noticeable problems and with good graphics settings. While playing GPU temperature didn't raised more than 6-7°C from starting point (never reached 50°C).  I believe you can play most modern games with such configuration and not very big resolutions without problems.


So this is it about this system. I hope you enjoyed these articles and found them helpful. Thank you for reading.