PC Review


Reply
Thread Tools Rate Thread

How bad is SMP with 2 different processor speeds?

 
 
Norm Dresner
Guest
Posts: n/a
 
      16th May 2004
I have a dual-capable SBC CPU board which accepts Socket 370 CPUs and I
happen to have 2 Pentium III cpus, one is 700MHz and the other is 800MHz.
What are the chances that I'd be able to run, say, Linux or Win2K with this
combination?

TIA
Norm

 
Reply With Quote
 
 
 
 
Andrzej Popowski
Guest
Posts: n/a
 
      16th May 2004
Sun, 16 May 2004 11:15:33 GMT, "Norm Dresner" <(E-Mail Removed)> wrote:

>I have a dual-capable SBC CPU board which accepts Socket 370 CPUs and I
>happen to have 2 Pentium III cpus, one is 700MHz and the other is 800MHz.
>What are the chances that I'd be able to run, say, Linux or Win2K with this
>combination?


This is not a proper setup, but IMHO should work OK.

There could be problems if this CPUs have different supply voltage or
FSB frequency. In this case results would depend on motherboard
hardware.


--
Pozdrowienia

Andrzej Popowski
 
Reply With Quote
 
Tony Hill
Guest
Posts: n/a
 
      16th May 2004
On Sun, 16 May 2004 11:15:33 GMT, "Norm Dresner" <(E-Mail Removed)>
wrote:
>I have a dual-capable SBC CPU board which accepts Socket 370 CPUs and I
>happen to have 2 Pentium III cpus, one is 700MHz and the other is 800MHz.
>What are the chances that I'd be able to run, say, Linux or Win2K with this
>combination?


Assuming they run at the same voltage and bus speed, chances are about
50/50. Some motherboards will do it, some will not. The operating
systems themselves should be able to handle it, but some drivers might
be problematic.

-------------
Tony Hill
hilla <underscore> 20 <at> yahoo <dot> ca
 
Reply With Quote
 
Triffid
Guest
Posts: n/a
 
      17th May 2004
Norm Dresner wrote:

> I have a dual-capable SBC CPU board which accepts Socket 370 CPUs and I
> happen to have 2 Pentium III cpus, one is 700MHz and the other is 800MHz.
> What are the chances that I'd be able to run, say, Linux or Win2K with this
> combination?
>
> TIA
> Norm
>


I have experimented with mis-matched PIII CPUs a few times and tend to
agree with Tony - the chances of it working reliably are no better than
50/50.

Most dual boards display a BIOS message indicating the family, core
speed, and number of processors detected on boot. IME it works better if
the BIOS reports the core speed of the slower processor, i.e. switch the
CPUs around if the BIOS sees the faster one.

 
Reply With Quote
 
Norm Dresner
Guest
Posts: n/a
 
      17th May 2004
"Triffid" <(E-Mail Removed)> wrote in message
news:6tTpc.1835$(E-Mail Removed)...
> Norm Dresner wrote:
>
> > I have a dual-capable SBC CPU board which accepts Socket 370 CPUs and I
> > happen to have 2 Pentium III cpus, one is 700MHz and the other is

800MHz.
> > What are the chances that I'd be able to run, say, Linux or Win2K with

this
> > combination?
> >
> > TIA
> > Norm


I dug the CPUs out of the carton and looked closely at them.
One CPU is clearly marked
750/256/100/1.65v
which I assume is a 750MHz w/256 K cache, 100MHz

The other is marked
RB80526P4600256
7007A330-1672
I beleive this is a 600 MHz and I'm interpreting the 256 to be the same as
in the 750. But the voltage? I'm guessing 3.30v -- Is this correct?

If one is 3.3v and the other is 1.65v then these two CPUs will definitely
not work on a dual board, right?

TIA
Norm

 
Reply With Quote
 
Triffid
Guest
Posts: n/a
 
      18th May 2004


Norm Dresner wrote:

> "Triffid" <(E-Mail Removed)> wrote in message
> news:6tTpc.1835$(E-Mail Removed)...
>
>>Norm Dresner wrote:
>>
>>
>>>I have a dual-capable SBC CPU board which accepts Socket 370 CPUs and I
>>>happen to have 2 Pentium III cpus, one is 700MHz and the other is

>
> 800MHz.
>
>>>What are the chances that I'd be able to run, say, Linux or Win2K with

>
> this
>
>>>combination?
>>>
>>>TIA
>>> Norm

>
>
> I dug the CPUs out of the carton and looked closely at them.
> One CPU is clearly marked
> 750/256/100/1.65v
> which I assume is a 750MHz w/256 K cache, 100MHz


Yup.

> The other is marked
> RB80526P4600256
> 7007A330-1672


That's an Intel order code, which AFAIK doesn't tell you any more than
core speed and cache (which you've correctly interpreted) unless you can
find it at intel.com (I couldn't).

All Intel CPUs should have an sSpec number on them somewhere - 5
character alphanumeric, first character "S". Find those, then plug them
in at processorfinder.intel.com for all the gory details.

> I beleive this is a 600 MHz and I'm interpreting the 256 to be the same as
> in the 750. But the voltage? I'm guessing 3.30v -- Is this correct?


Can't be. A 600Mhz PIII has either a Katmai (2.0v) or Coppermine
(1.6-1.8v) core.

> If one is 3.3v and the other is 1.65v then these two CPUs will definitely
> not work on a dual board, right?


IME a voltage difference is not a problem as dual boards typically have
separate Vcore regulators for each CPU and are therefore able to honour
mismatched VID requests.

>
> TIA
> Norm
>


 
Reply With Quote
 
Norm Dresner
Guest
Posts: n/a
 
      18th May 2004
"Triffid" <(E-Mail Removed)> wrote in message
news:91fqc.26529$(E-Mail Removed)...
> Norm Dresner wrote:
> > "Triffid" <(E-Mail Removed)> wrote in message
> > news:6tTpc.1835$(E-Mail Removed)...
> >>Norm Dresner wrote:
> >>>I have a dual-capable SBC CPU board which accepts Socket 370 CPUs and I
> >>>happen to have 2 Pentium III cpus, one is 700MHz and the other is
> >>>800MHz.
> >>>What are the chances that I'd be able to run, say, Linux or Win2K with

this combination?
> >>>TIA
> >>> Norm

> >
> > I dug the CPUs out of the carton and looked closely at them.
> > One CPU is clearly marked
> > 750/256/100/1.65v
> > which I assume is a 750MHz w/256 K cache, 100MHz

> Yup.
> > The other is marked
> > RB80526P4600256
> > 7007A330-1672

> That's an Intel order code, which AFAIK doesn't tell you any more than
> core speed and cache (which you've correctly interpreted) unless you can
> find it at intel.com (I couldn't).
> All Intel CPUs should have an sSpec number on them somewhere - 5
> character alphanumeric, first character "S". Find those, then plug them
> in at processorfinder.intel.com for all the gory details.
>

Thanks for the URL. I found the sSpec # on the chip and it's
600MHz / 256K / 100 MHz / 1.65v
so the voltages match after all.

As for the board -- since it's a PICMG CPU board and not a motherboard I
wouldn't count on having enough room to have two independent VRs -- but it's
possible. I can't get to the board right now to check but I will, though
it's no longer an issue.

Thanks
Norm

 
Reply With Quote
 
Triffid
Guest
Posts: n/a
 
      19th May 2004


Norm Dresner wrote:

> "Triffid" <(E-Mail Removed)> wrote in message
> news:91fqc.26529$(E-Mail Removed)...
>
>>Norm Dresner wrote:
>>
>>> "Triffid" <(E-Mail Removed)> wrote in message
>>>news:6tTpc.1835$(E-Mail Removed)...
>>>
>>>>Norm Dresner wrote:
>>>>
>>>>>I have a dual-capable SBC CPU board which accepts Socket 370 CPUs and I
>>>>>happen to have 2 Pentium III cpus, one is 700MHz and the other is
>>>>>800MHz.
>>>>>What are the chances that I'd be able to run, say, Linux or Win2K with

>
> this combination?
>
>>>>>TIA
>>>>> Norm
>>>
>>>I dug the CPUs out of the carton and looked closely at them.
>>>One CPU is clearly marked
>>> 750/256/100/1.65v
>>>which I assume is a 750MHz w/256 K cache, 100MHz

>>
>>Yup.
>>
>>>The other is marked
>>> RB80526P4600256
>>> 7007A330-1672

>>
>>That's an Intel order code, which AFAIK doesn't tell you any more than
>>core speed and cache (which you've correctly interpreted) unless you can
>>find it at intel.com (I couldn't).
>>All Intel CPUs should have an sSpec number on them somewhere - 5
>>character alphanumeric, first character "S". Find those, then plug them
>>in at processorfinder.intel.com for all the gory details.
>>

>
> Thanks for the URL. I found the sSpec # on the chip and it's
> 600MHz / 256K / 100 MHz / 1.65v
> so the voltages match after all.
>
> As for the board -- since it's a PICMG CPU board and not a motherboard I
> wouldn't count on having enough room to have two independent VRs -- but it's
> possible. I can't get to the board right now to check but I will, though
> it's no longer an issue.
>
> Thanks
> Norm
>

They're both Coppermines, speed discrepancy is only 150Mhz - it might work!

Let us know...

 
Reply With Quote
 
 
 
Reply

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Processor speeds Jim Brown Windows Vista Hardware 2 18th Oct 2007 12:44 PM
Processor speeds... Robert Bodling Windows XP General 10 4th Mar 2004 09:48 PM
Processor Speeds Sam Windows XP Help 1 24th Nov 2003 11:06 PM
Processor Speeds Kendo General 4 29th Sep 2003 04:18 PM
Processor speeds Colin Bearfield Computer Hardware 3 1st Sep 2003 05:27 AM


Features
 

Advertising
 

Newsgroups
 


All times are GMT +1. The time now is 02:46 AM.