Low Cost/Power HPC

The low power Intel Atom offers some interesting possibilities for HPC. Does it make sense to try this approach?

In my last column, I mentioned the idea of disposable HPC. The concept is based on building clusters using low cost nodes (less than $500 each). Because lower cost nodes will run slower and have less cores than the big server nodes, they would need to be smaller and use much less power. They will also need a lowerThermal Design Power (TDP) to accommodate dense packaging designs.

Is such a cluster possible? Before we take a look at some real options hitting the market, let’s take a look at some numbers. In a recent article at Extremetech, they discuss a paper by researchers at Harvard and Microsoft that seeks to prove that a small, power-efficient core like the Intel Atom chip can be better suited for search applications. The paper is due to be presented at the International Symposium on Computer Architecture in Saint-Malo, France, on June 19.

According to Extremetech, the paper states that with an average power consumption of 3.2 watts, the Atom (single-core 1.6 GHz Diamondville) is 19.5 times more power-efficient than a Xeon (L5420 quad-core, 2.5-GHz, Harpertown), which consumes 62.5 watts on average. The Xeon, meanwhile, outperformed the Atom by 3.9 times for search tasks.

On a cost basis, the researchers estimated an Atom server would cost about $375, versus $1,210 for a Xeon server, with the only variables being the prices of the processor and motherboard. While these numbers looked interesting, I wanted to try my own comparison for HPC purposes. Keep in mind this is a back of the envelope comparison and there are many other issues that may affect performance. My goal is to get a general idea of how the processors compare in terms of HPC.

I went to Intel’s website and got most of the information for both an Atom D510 (dual core, 1.66 GHz) and Xeon 5570 (quad-core, 2.93 GHz). Both of these represent currently available parts and I used Intel’s stated price for quantities of 1000. Next, I tried to find floating point results for both processors. There are no SPEC numbers for the Atom, but I did find some POV numbers for both the D510 and an i7 870 running at 2.93GHz. (POV is a rendering program that uses heavy floating point processing). Since the i7 and Xeon are very similar, it seems reasonable to use the POV number as a measure of performance (remembering it is a single measurement). The results of my comparison are in the Table below. Note for the TDP/Perf and Price/Perf ratios, lower is better.

Processor Clock
Cores TDP
(qty 1000)
(POV 3.7 SMP)
TDP/Perf Price/Perf
Atom D510 1.66 dual 13 $63 470.6 .028 .13
Xeon 5570 2.93 quad 95 $1386 3603 .026 .39
1.8 2 7.3 22 7.7 .93 3

The results are rather interesting. The Nehalem Xeon runs 1.8 times faster, generates 7.3 times as much heat and costs 22 times as much as the D510 Atom. The Xeon performance is 7.7 times faster, but when you factor in the price-to-performance the Atom is 3 times better than the Xeon solution. Interestingly, the TDP/performance ratios are almost identical for both processors. Thus, there is no real power advantage with either processor.

The Atom has a clear price-to-performance advantage over the Xeon, however, it is not quite that simple. Since you need at least 8 Atom processors to do the work of one Xeon, you need 8 separate nodes. The cost per Atom node includes things like motherboards, memory, etc. so the 3X price to performance advantage may quickly evaporate. It may be possible to narrow the performance gap or there may be better performing floating point applications suited for the Atom, but for now we’ll use this data as a first approximation. Also note, I have not considered the fact that with 8 Atom nodes, there is 8 MB of total distributed cache available to a parallel application.

Intel has released six Pineview Atom chips (and announced two more). The following table shows the specifications for these processors. Note that Total TDP is for the processor and the supporting chip-set.

Model Cores Cache Speed Memory CPU TDP Total TDP
Atom N450 single 512K 1.66 GHz DDR2 5.5 Watts 7 Watts
Atom N455 single 512K 1.66 GHz DDR2/3 5.5 Watts 7 Watts
Atom N470 single 512K 1.83 GHz DDR2 6.5 Watts 8 Watts
Atom N475 single 512K 1.83 GHz DDR2/3 6.5 Watts 8 Watts
Atom D410 single 512K 1.66 GHz DDR2 10 Watts 12 Watts
Atom D425* single 512K 1.66 GHz DDR3 ~10 Watts ~12 Watts
Atom D510 dual 1MB 1.66 GHz DDR2 13 Watts 15 Watts
Atom D525* dual 1MB 1.66 GHz DDR3 ~13 Watts ~15 Watts

*The D425 and the D525 have been announced for a June 2010 release)

Because Atoms are destined to end up in small low power designs, there is no need for a huge motherboard. Indeed, many Atom motherboards use the Mini ITX form factor. Most users are familiar with the ATX form factor where the motherboard measures 12×9.6 inches (305×244 mm). Developed by VIA Technologies, a Mini ITX motherboard measures 6.7 inches square (170mm), which is roughly 40% the size of an ATX motherboard. Most Mini ITX systems are designed to be passively cooled and are intended for low power operation such as desktops, routers, and even servers.

There is currently a large number of Mini ITX motherboards available to Linux users. As listed at the LinuxTECH.net site there are over 20 Mini ITX boards currently available. Almost all of these boards are in the $100 price range. Of particular interest is the Asus Hummingbird. The Hummingbird is designed as a server board and offers optional remote management (IPMI) capabilities, provides dual Intel GigE network interfaces, and a 10/100 management NIC.

There are also some other factors that may make Atom nodes attractive. Lower power and less heat means less fans and even passive cooling for the processor. This removes the cost and space from case designs and reduces the need to be concerned about broken fans. It is not too difficult to envision shared power supplies and blades, using Mini ITX motherboards, to help increase density and lower the packaging cost.

Of course, the choice of processor and interconnect depends on your application. Low power/high node count clusters are certainly possible right now. For those applications that require low latency communications, Xeon servers and InfiniBand are still the way to go. For other applications, low power solutions may provide better price-to-performance than one might expect, but the devil, as the say, is in the benchmarks.

Comments on "Low Cost/Power HPC"


The numbers in the comparison are mixed up in places — the price ratio should be 22:1, the performance ratio 7.7:1, and the TDP 7.3:1


quite surprising that the atom is more eficient tahn the Xeon.
well, a quad core Xeon server is preferable than 22 mini ITX nodes i think.
One of the problem is the cabling for connecting 22 nodes (if you build them independently), you will need a 24 port ethernet switch along with the cables to achieve the same performance with Xeon, instead of another problems like space requirement, and maintenance.
Unless, someone start to think about multi processor atom server (a blade with 16 atom processors for example), which is absolutely much more neat.


Thanks Nir!

I got my numbers mixed up in my HTML table formatting. I fixed
the table and now it is correct. I also re-checked all the numbers. (assuming I hit the right keys on my trusty old HP 15C). The big difference is that with POV the Xeon is 7.7 times faster, not 22 as I first reported. While this does not change some of the cost issues I mentioned, it certainly does put a handful Atom within striking distance of the Xeon.




Useful to anyone wishing to pursue this further is to examine the work over the decade. Significant papers by W. Feng at Los Alamos justify small clusters. Also, though not realized as yet, was the proposed Atom cluster \”Molecule\” at SGI.

Thanks for covering this. I think you are on to important subject — I remember the Cray 1 hiding it refrigeration 10x its size in the floor and benches surrounding it.


Well, I too was wondering whether the idea of disposing HPC’s would work with bcm software as you said in your previous post. The main advantage of it from what I see is that it can run really slow as it has its base on nodes which are pretty cheap by the way. Anyway, before we come to a conclusion that it would work as we expect, we need to take some factors into account. Since it is a low cost node, chances are that it would often get damaged and a need of constant replacement is going to be problem.


Major thanks for the post.Really thank you! Cool.


Hello Web Admin, I noticed that your On-Page SEO is is missing a few factors, for one you do not use all three H tags in your post, also I notice that you are not using bold or italics properly in your SEO optimization. On-Page SEO means more now than ever since the new Google update: Panda. No longer are backlinks and simply pinging or sending out a RSS feed the key to getting Google PageRank or Alexa Rankings, You now NEED On-Page SEO. So what is good On-Page SEO?First your keyword must appear in the title.Then it must appear in the URL.You have to optimize your keyword and make sure that it has a nice keyword density of 3-5% in your article with relevant LSI (Latent Semantic Indexing). Then you should spread all H1,H2,H3 tags in your article.Your Keyword should appear in your first paragraph and in the last sentence of the page. You should have relevant usage of Bold and italics of your keyword.There should be one internal link to a page on your blog and you should have one image with an alt tag that has your keyword….wait there’s even more Now what if i told you there was a simple WordPress plugin that does all the On-Page SEO, and automatically for you? That’s right AUTOMATICALLY, just watch this 4minute video for more information at. Seo Plugin


Perfectly indited content , regards for information.


That is the end of this report. Right here you?ll find some websites that we assume you will enjoy, just click the hyperlinks.


Every once in a when we decide on blogs that we study. Listed beneath would be the latest web sites that we opt for.


1On5hy say about this article, in my view its in fact


Please stop by the web-sites we follow, including this a single, because it represents our picks from the web.


Here are a number of the sites we suggest for our visitors.


Leave a Reply

Your email address will not be published. Required fields are marked *


You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>