Wednesday, January 20, 2010

Evaluating PC computing hardware

Summary: the newest processors (e.g. Intel’s Core i7 CPUs) have much to offer over older technologies, including more raw computing power, improved energy efficiency, and reduction of total cost of ownership (TCO).    

Where it all started…

I recently decided to entertain myself by starting a new analytics project that will look at huge quantities of financial data from the stock market.   I have some theories about how the markets move that I’d like to test out, and testing these theories will take a bunch of computing power.

imageWhile my trusty Dell PowerEdge 400SC (“BUCKY”, ca. 2004) is still admirably snappy for almost everything else, it does not appear to be a match for sifting millions of rows of stock market data.  I am actually in awe of how well this machine still performs, given that I bought it about 6 years ago – April 14th, 2004 to be exact.

==> Look for an upcoming post on How to Buy a New PC where I’ll tell you how I buy computers which last for years & still run fast.

eBay: a smorgasbord of computing hardware

I started my hardware upgrade quest by checking out the Dell server hardware on eBay.   There is a vast selection, hundreds or even thousands of machines, and it is truly amazing what you can buy for only $200 or so. 

For example, a Dell PowerEdge 2850 with dual Xeon Dell PowerEdge 2850processors at 3GHz and a whopping 8GB of RAM; onboard SCSI RAID support for running high-performance disks in a “mirrored” array (essential to eliminate any single point of failure);  ECC memory, which is more reliable than regular desktop memory; and fast, reliable SCSI hard drives, which last far longer than the cheap commodity consumer drives that Best Buy will sell you, after marking them up significantly to pay for the lights and the space and all those big-screen TVs that seem to be blaring all the time.  (These server-class SCSI hard drives are however typically much smaller than the 500GB and larger sizes we’ve become accustomed to in the consumer desktop space.)

So eBay has some serious server-class hardware.  It really made me drool. I almost pulled the trigger on a few of those PowerEdge 2850’s that had 8 to 12 GB of memory, for $200, delivered.  You can hardly buy 12GB of RAM alone for $200!  But why so cheap?    After all, markets are “efficient,” aren’t they?  I wanted to understand…

Space, time, and energy

imageAfter puzzling on it for a couple of days and surfing around, I came up with the following conclusions.  While these machines offer a whole lot of quality and power, they have at least two drawbacksenergy efficiency and computing power.  

Most of the folks who work with these machines have them packed into server datacenters, running under reasonable load (one would assume).   The CPU, the most power-hungry component of a computer (in general), uses more energy when under load.   When you look at total cost of ownership (TCO), it’s not exactly cheap to keep them powered up and cooled down.  

==> The numbers vary, but I would ballpark the cost of a watt-year (one watt for one year) at about $1 per year, assuming $0.10 per kilowatt-hour.  So an older machine that burns 150 to 200 watts more than a more efficient, newer one will cost $150-$200 more per year.  Across the lifetime of the machine, that’s $600 to $800.

imageThe kicker is that the newer servers sport the latest multi-core processor designs from Intel and AMD.    These multi-core designs (quad-core in this case) operate much more efficiently and run much faster.  So when a new quad-core server is brought in, it can retire possibly three or four older servers.   Now we’re talking $1,500 to $2,000 in savings over the next three to four years in energy costs along.  In addition, server datacenters can now pack three to four times more computing power in the same expensive rack space.  

Link: Study looks at payback period for server consolidation of Dell PowerEdge 2850’s


Back at home, my stock market analysis project is significantly “compute-bound,” requiring more processor power than my PowerEdge 400SC can throw at it. In this case, a new server can do what an older server simply can’t.    Dude, I have just justified getting a new Dell! 

In my next post, I’ll chronicle how I select a new Dell machine that will do everything I need it to. 

Update 2/11/2010:  see post Choosing a new CPU: Core i7-920 vs. Core i7-860 on my computing blog.

More Reading…

Virtualization technologies (VT) offer IT organizations and datacenters huge savings because they improve energy efficiency and lower costs;  this I would imagine is a major driver in pushing down the price of older computing hardware (which does not support VT as well).

Interesting related entry on the cost of computing power(Wikipedia):

“Hardware costs for low cost supercomputers may be less significant than energy costs when running continuously for several years.”

1 comment:

  1. great read. I would love to follow you on twitter.