Dual processor vs. dual core

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

For performance and tax reasons I really should build a new "God box"
this year. In the past, I've built ASUS mobo-based dual Pentium II and
Pentium III boxes, and have been very happy with their performance
when multi-tasking. I use multi-thread- and multi-processor-aware apps
and OS, and know how to tweak for maximum sustainable speed.

Looking forward in the next six months, should I consider dual-core or
dual processor? Ideally, I use these machines for three to four years:
should I build with an eye to 64-bit OS needs? Opteron or Xeon or the
new Smithfield? Boards with good reputations (I've found ASUS
dependable for many years now).

Suggestions or just blue-skying is welcome. Money isn't a huge issue
as I change up machines less often than a true hobbyist: I require raw
business app power and multi-tasking ability, not gaming and not video
production, but yes, some high-end graphics.

Thanks,

R.
10 answers Last reply
More about dual processor dual core
  1. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    You might want to read up on dual opterons. My understand is this chip
    set has memory allocated for each CPU such that both can use their own
    ram at the same time:
    http://www.tyan.com/products/html/thunderk8we.html
    There is a provision for one CPU to read the other CPU's memory, and
    vice versa. This eliminates a bottle neck in dual processors. It seems
    dual core won't have this capability.

    Personally, after building dual CPU systems, I just don't think it is
    worth the extra cost. Better to upgrade later. The only thing building
    a super system does is it prevents the downtime as you migrate from one
    system to the other, which often isn't trivial. You know how much work
    it is to get a system just right.
  2. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    rhys <rhys@nospam.com> wrote:

    > ... I use multi-thread- and multi-processor-aware apps
    > and OS, and know how to tweak for maximum sustainable speed.
    > Looking forward in the next six months, should I consider
    > dual-core or dual processor? ...
    > Suggestions or just blue-skying is welcome.

    Seems to me that would be multi-processor. One thing for sure,
    IMO, is that shopping online is the way to go for a system. Like
    they used to say, let your fingers do the walking. Have fun.
  3. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    The major problem with Dual core is that it 'shares' things like the L1/L2
    cache....imagine the performance loss when both cores running at high
    capacity...

    I would definately go with the Opterons. 64bit and integrated on-chip memory
    controller being 2 of the biggest benefits.

    "rhys" <rhys@nospam.com> wrote in message
    news:46rr51deti8pdan3bro2rumthgal3ssub6@4ax.com...
    > For performance and tax reasons I really should build a new "God box"
    > this year. In the past, I've built ASUS mobo-based dual Pentium II and
    > Pentium III boxes, and have been very happy with their performance
    > when multi-tasking. I use multi-thread- and multi-processor-aware apps
    > and OS, and know how to tweak for maximum sustainable speed.
    >
    > Looking forward in the next six months, should I consider dual-core or
    > dual processor? Ideally, I use these machines for three to four years:
    > should I build with an eye to 64-bit OS needs? Opteron or Xeon or the
    > new Smithfield? Boards with good reputations (I've found ASUS
    > dependable for many years now).
    >
    > Suggestions or just blue-skying is welcome. Money isn't a huge issue
    > as I change up machines less often than a true hobbyist: I require raw
    > business app power and multi-tasking ability, not gaming and not video
    > production, but yes, some high-end graphics.
    >
    > Thanks,
    >
    > R.
  4. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    On 14 Apr 2005 00:13:54 -0700, miso@sushi.com wrote:

    >You might want to read up on dual opterons.

    I have been. They intrigue me at both the price and performance point.
    I think Xeons could be cheaper and cooler.

    My understand is this chip
    >set has memory allocated for each CPU such that both can use their own
    >ram at the same time:
    >http://www.tyan.com/products/html/thunderk8we.html
    >There is a provision for one CPU to read the other CPU's memory, and
    >vice versa. This eliminates a bottle neck in dual processors.

    Yes, it makes sense to max out the RAM then.


    It seems
    >dual core won't have this capability.

    That's why I've been wondering if it's an "applicable to me"
    technology. I use the benefits of dual CPUs constantly, but I'm a sort
    of niche market, which is why I custom assemble in the first place.
    >
    >Personally, after building dual CPU systems, I just don't think it is
    >worth the extra cost. Better to upgrade later. The only thing building
    >a super system does is it prevents the downtime as you migrate from one
    >system to the other, which often isn't trivial. You know how much work
    >it is to get a system just right.

    Yes, the tweaking and whatnot takes time and a certain amount of
    expertise and expermentation. Still, I can get two sub-maximal CPUs in
    terms of speed and cost to totally outperform the "fastest" single CPU
    in the apps and environment I use.

    Thanks,
    R.
  5. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    On Thu, 14 Apr 2005 09:27:30 GMT, "paak" <paak@nbnet.nb.ca> wrote:

    >The major problem with Dual core is that it 'shares' things like the L1/L2
    >cache....imagine the performance loss when both cores running at high
    >capacity...
    >
    >I would definately go with the Opterons. 64bit and integrated on-chip memory
    >controller being 2 of the biggest benefits.

    Assuming I go with a pair of them, any suggestions as to boards,
    chipsets, best RAM and appropriate power supplies? I don't care if I
    have to go WTX, but as I won't run more than one video card and no
    more than three drives, I wouldn't mind avoiding "specialty" cabling
    and connectors, i.e. sticking with the ATX form factor (now that BTX
    seems to be in a coma, that is).

    I don't overclock my main rigs, by the way, and I am putting a premium
    on my next dual CPU rig being as quiet as possible.

    R.

    >
    >"rhys" <rhys@nospam.com> wrote in message
    >news:46rr51deti8pdan3bro2rumthgal3ssub6@4ax.com...
    >> For performance and tax reasons I really should build a new "God box"
    >> this year. In the past, I've built ASUS mobo-based dual Pentium II and
    >> Pentium III boxes, and have been very happy with their performance
    >> when multi-tasking. I use multi-thread- and multi-processor-aware apps
    >> and OS, and know how to tweak for maximum sustainable speed.
    >>
    >> Looking forward in the next six months, should I consider dual-core or
    >> dual processor? Ideally, I use these machines for three to four years:
    >> should I build with an eye to 64-bit OS needs? Opteron or Xeon or the
    >> new Smithfield? Boards with good reputations (I've found ASUS
    >> dependable for many years now).
    >>
    >> Suggestions or just blue-skying is welcome. Money isn't a huge issue
    >> as I change up machines less often than a true hobbyist: I require raw
    >> business app power and multi-tasking ability, not gaming and not video
    >> production, but yes, some high-end graphics.
    >>
    >> Thanks,
    >>
    >> R.
    >
  6. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    Just to be clear here, it's not a matter of maxing out on ram as much
    as each processor having a direct path to their own ram. That is why
    there are so many memory sockets on the board. I believe this is unique
    to the Opteron, i.e. you won't have the same memory structure using
    Xeon processors.

    Some programs really benefit from dual CPUs, such as photoshop. But you
    don't get 2x the speed. A few programs actually are worse under dual
    CPUs, but this is pretty rare. Tom's hardware has benchmarks on dual
    CPU systems and generally you aren't getting much bang for your buck.
  7. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    On the coming Dual Core AMD 64 CPUs, the L1 cash will be separae, and the
    L2 will be shared, and there are advantages in that. There will be a
    "crossbar switch" between them, on die between the CPUs and the memory
    controller. It looks like it will be a great thing. I seem to remember
    that there was some advantage to having the crossbar switch and shared L2
    cache, I think it was because round trips were reduced or something, but I
    might be wrong.

    On Thu, 14 Apr 2005 09:27:30 GMT, paak wrote:

    > The major problem with Dual core is that it 'shares' things like the L1/L2
    > cache....imagine the performance loss when both cores running at high
    > capacity...
    >
    > I would definately go with the Opterons. 64bit and integrated on-chip memory
    > controller being 2 of the biggest benefits.
    >
    > "rhys" <rhys@nospam.com> wrote in message
    > news:46rr51deti8pdan3bro2rumthgal3ssub6@4ax.com...
    >> For performance and tax reasons I really should build a new "God box"
    >> this year. In the past, I've built ASUS mobo-based dual Pentium II and
    >> Pentium III boxes, and have been very happy with their performance
    >> when multi-tasking. I use multi-thread- and multi-processor-aware apps
    >> and OS, and know how to tweak for maximum sustainable speed.
    >>
    >> Looking forward in the next six months, should I consider dual-core or
    >> dual processor? Ideally, I use these machines for three to four years:
    >> should I build with an eye to 64-bit OS needs? Opteron or Xeon or the
    >> new Smithfield? Boards with good reputations (I've found ASUS
    >> dependable for many years now).
    >>
    >> Suggestions or just blue-skying is welcome. Money isn't a huge issue
    >> as I change up machines less often than a true hobbyist: I require raw
    >> business app power and multi-tasking ability, not gaming and not video
    >> production, but yes, some high-end graphics.
    >>
    >> Thanks,
    >>
    >> R.
  8. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    On 14 Apr 2005 11:47:38 -0700, miso@sushi.com wrote:

    >Just to be clear here, it's not a matter of maxing out on ram as much
    >as each processor having a direct path to their own ram. That is why
    >there are so many memory sockets on the board. I believe this is unique
    >to the Opteron, i.e. you won't have the same memory structure using
    >Xeon processors.

    I think I understood that, but thank you for reiterating it. I have
    been hearing generally that Opteron is a better deal not just in price
    and performance but in clever engineering like this. What boards do
    you recommend?
    >
    >Some programs really benefit from dual CPUs, such as photoshop.

    This would be a 2-D graphics workstation, using latest Photoshop (with
    lots of batch processing), InDesign, Quark, Illustrator, Pagemaker,
    and I do a LOT of Acrobat distills and PostScript work.

    If I poll my e-mail or try to load a webpage during that sort of thing
    on a single CPU machine, they go into a corner to have a good cry.

    I realize that dual CPUs aren't the answer for many, but I've had them
    since '97 and I run a mix of apps that recognize and use them
    effectively under Windows NT (in '97) and now Windows 2000.


    But you
    >don't get 2x the speed.

    Understood. What you do get is the ability to run more programs in the
    background without incurring page faults and exceptions.

    A few programs actually are worse under dual
    >CPUs, but this is pretty rare. Tom's hardware has benchmarks on dual
    >CPU systems and generally you aren't getting much bang for your buck.

    Except for me. Trust me on this. I haven't read anything in the last
    two years about OSes and single processor improvements that seems to
    negate the immediate benefits I get in desktop publishing and graphic
    design from dual CPUs and a decent video card and bags of RAM.

    The thing I can economize on are the hard drives, DVD drives, the
    audio (basic) and I have a box of networking gear and retired routers
    already.

    R.
  9. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    On Fri, 15 Apr 2005 07:58:11 GMT, signmeuptoo
    <signmeuptoo_no_spam@earthlink.net> wrote:

    >On the coming Dual Core AMD 64 CPUs, the L1 cash will be separae, and the
    >L2 will be shared, and there are advantages in that. There will be a
    >"crossbar switch" between them, on die between the CPUs and the memory
    >controller. It looks like it will be a great thing. I seem to remember
    >that there was some advantage to having the crossbar switch and shared L2
    >cache, I think it was because round trips were reduced or something, but I
    >might be wrong.

    Thanks for this. I would love to hear from someone already using dual
    Xeon or Opterons in the real world, and where they see an upgrade
    path.

    R.
  10. Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

    First of all, I feel like an idiot for not suggesting you visit
    http://www.2cpu.com/
    I totally forgot about this website.

    Most of the modern boards have one or two gigabit ethernets and audio
    installed, so there isn't much to save buy owning such gear. .I'd go
    with the Tyan board I put in the other post.

    The only thing is these boards like to be stuff with identical RAM
    modules. Since 32 bit windows can only handle 4G of RAM, you will have
    to stuff all the sockets of the board with very small modules for all
    the fancy features to work. Memory always has a sweet spot, i.e. there
    is a spot where the cost per bit is the cheapest. I suspect you will be
    on the low side of that curve. Maybe you should wait for the 64 bit OS
    to come out.

    I think if you are getting page faults, the problem is lack of ram and
    not lack of a dual CPU. That is, you are doing swapping of memory and
    perhaps the swap area of the disk is not so reliable. My notebook PC is
    not a dually, and I don't have such problems.

    You may be aware that some programs or hadware don't work with dual
    processors. I had this trouble with my sound blaster live until they
    fixed the problem. Some adaptec gear has disclaimers on dual CPU
    operation as well.

    Regarding disk drives. you might as well set up a raid system and
    mirror the drives. The raid boards that you can stuff with ram should
    get you an additional boost. This is where I'd spend the money instead
    of going dual. However, it's really not that much more expensive for a
    second CPU if it gives you some peace of mind.
Ask a new question

Read More

Homebuilt Dual Processor Dual Core Systems