Dual Core or Quad Core?

[Warren Luebkeman]

This is the motherboard I'm looking at: 
http://www.intel.com/design/servers/boards/s5000PSL/index.htm

Here is the info on the front side bus.  It says 1066 / 1333¹ MHz dual 
independent buses, which sounds pretty good.  What do you guys think?
http://www.intel.com/products/chipsets/5000p/index.htm






On Friday 29 June 2007 2:20 pm, Warren Luebkeman wrote:
> On Friday 29 June 2007 11:58 am, Christopher Chisholm wrote:
> > Derek Atkins wrote:
> > > "Tom Buskey" <tom at buskey.name> writes:
> > >> A few points:
> > >>
> > >> The Macintosh community had debates in the past about SMP vs single.
> > >> Generally they think a dual 500 MHz is roughly like a single 700MHz.
> > >> From that subjective information, I'd say more cores that are slightly
> > >> slower are better.
> > >
> > > This is probably true, as each core can be working on a separate
> > > process so you have less context switching.
> > >
> > >> I've felt that dual CPUs have lower latency when multitasking.  The OS
> > >> runs on one CPU, software raid (why spend more for a dedicated
> > >> hardware raid card?), your App on another, etc.  IMHO latency is more
> > >> important then throughput for interactive use.
> > >
> > > This is probably related to fewer context switches, but keep in mind
> > > the memory bandwidth.
> > >
> > >> I've been looking at a VMware ESX server.  it's licensed per 2 CPUs. 
> > >> A 4 core is the same as a single or dual core in their licensing.  I'm
> > >> finding with that, a dual quad core is cheaper then adding ram + 1 cpu
> > >> to 2 systems with 3 single core cpus between them.
> > >>
> > >> Those 1.6GHz CPUs might use less power & generate less heat.
> > >
> > > "might" being the key operative word here.  Check the specs.
> > >
> > >> The real limit on your application will likely be I/O.  Bus speed
> > >> (FSB), network, disk speed, memory speed, etc.  How much data are they
> > >> moving around? More RAM will help more then CPU GHz also.
> > >
> > > Keep in mind the memory bus issues.  In particular looking at Intel vs
> > > AMD Quad-cores, the Intel quads are effectively two Dual-cores in a
> > > single package and they share a memory controller, whereas the AMD
> > > quads will theoretically each have a memory controller.  What this
> > > means is that you get higher memory throughput (and lower latency) on
> > > AMDs than Intels.  I just don't know which applications this effects.
> >
> > I've always liked the AMD architecture because of their "hypertransport
> > bus", which is basically a fancy way of saying that certain things a
> > dedicated bus.  Intel's architecture (unless something has recently
> > changed) still has everything going through the front side bus.  AMD's
> > processors have a memory controller integrated on each processor itself,
> > along with a dedicated bus to the memory it uses.  So, you may need more
> > sticks of ram, but in theory the bus architecture is highly optimized
> > (the memory bus won't be affected by what's going on with the network,
> > HDDs, etc).
> >
> > For a single-user environment, it seems like benchmarks more or less
> > prove that the different isn't huge, but i could see how with 50 users
> > each doing their own thing AMD's approach may work better.  That's
> > purely a (somewhat) educated guess, it might not be true.
> >
> > As a side note, i know xeon heatsinks are screwed into the motherboard
> > for a nice solid connection, but all the other intel chips use what i
> > think is the worst idea ever conceived for a heatsink clip.  AMD's
> > heatsink fastening system feels so solid when you clamp it down, whereas
> > all the non-xeon heatsinks are kind of screwed in with cheap plastic
> > gadgets that everyone seems to have problems with.  This doesn't really
> > pertain to this issue since we're talking xeon, but i've never quite
> > been able to get over that... :-)
>
> Unfortunately the company I'm doing business with only works with Intel
> products.  We used to be an AMD only shop, but I really like doing business
> with this particular company.  The customer support is the most important
> thing at the end of the day!
>
> > > -derek
> >
> > -chris
> > _______________________________________________
> > gnhlug-discuss mailing list
> > gnhlug-discuss at mail.gnhlug.org
> > http://mail.gnhlug.org/mailman/listinfo/gnhlug-discuss/

-- 
Warren Luebkeman
Founder, COO
Resara LLC
1.888.357.9195
www.resara.com