Dual Athlon CPU detection..

Dual Athlon CPU detection..

[Thomas Davis]

I'm getting this in my /proc/cpuinfo:

[tdavis@lanshark tdavis]$ more /proc/cpuinfo
processor       : 0
vendor_id       : AuthenticAMD
cpu family      : 6
model           : 8
model name      : AMD Athlon(tm) MP 2200+
stepping        : 0
cpu MHz         : 1800.902
cache size      : 256 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 1
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
 pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow
bogomips        : 3547.13

processor       : 1
vendor_id       : AuthenticAMD
cpu family      : 6
model           : 8
model name      : AMD Athlon(tm) Processor
stepping        : 0
cpu MHz         : 1800.902
cache size      : 256 KB
fdiv_bug        : no
hlt_bug         : no
f00f_bug        : no
coma_bug        : no
fpu             : yes
fpu_exception   : yes
cpuid level     : 1
wp              : yes
flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov
 pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow
bogomips        : 3596.28
[tdavis@lanshark tdavis]$ uname -a
Linux lanshark.nersc.gov 2.6.4-rc1-mm1 #1 SMP Tue Mar 2 14:09:44 PST 2004 i686 athlon i386 GNU/Linux


Is this a bad CPU, or a kernel bug?

Re: Dual Athlon CPU detection..

[Mark]

On March 18, 2004 12:47 pm, Thomas Davis <tadavis@lbl.gov> wrote:
> I'm getting this in my /proc/cpuinfo:
>
> [tdavis@lanshark tdavis]$ more /proc/cpuinfo
> processor       : 0
> vendor_id       : AuthenticAMD
> cpu family      : 6
> model           : 8
> model name      : AMD Athlon(tm) MP 2200+
> stepping        : 0
> cpu MHz         : 1800.902
> cache size      : 256 KB
> fdiv_bug        : no
> hlt_bug         : no
> f00f_bug        : no
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 1
> wp              : yes
> flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca
> cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow
> bogomips        : 3547.13
>
> processor       : 1
> vendor_id       : AuthenticAMD
> cpu family      : 6
> model           : 8
> model name      : AMD Athlon(tm) Processor
> stepping        : 0
> cpu MHz         : 1800.902
> cache size      : 256 KB
> fdiv_bug        : no
> hlt_bug         : no
> f00f_bug        : no
> coma_bug        : no
> fpu             : yes
> fpu_exception   : yes
> cpuid level     : 1
> wp              : yes
> flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca
> cmov pat pse36 mmx fxsr sse syscall mp mmxext 3dnowext 3dnow
> bogomips        : 3596.28
> [tdavis@lanshark tdavis]$ uname -a
> Linux lanshark.nersc.gov 2.6.4-rc1-mm1 #1 SMP Tue Mar 2 14:09:44 PST 2004
> i686 athlon i386 GNU/Linux
>
>
> Is this a bad CPU, or a kernel bug?

AFAIK this information comes from the Bios. Some bioses don't verify that the 
second CPU as being an MP. It's been known for some time. Some people were 
using this to run 1 MP and 1 XP to save money on processors. However if you 
were to update your bios, it might start checking both for being MPs. 
Original bioses didn't even check for the first processor at one time but AMD 
complained and the bioses were modified.

-- 
Mark Lane, CET mailto:mark@harddata.com 
Hard Data Ltd. http://www.harddata.com 
T: 01-780-456-9771   F: 01-780-456-9772
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--> Ask me about our Excellent 1U Systems! <--

Re: Dual Athlon CPU detection..

[Willy Tarreau]

On Thu, Mar 18, 2004 at 01:52:34PM -0700, Mark wrote:
> On March 18, 2004 12:47 pm, Thomas Davis <tadavis@lbl.gov> wrote:
> >
> > Is this a bad CPU, or a kernel bug?
> 
> AFAIK this information comes from the Bios. Some bioses don't verify that the 
> second CPU as being an MP. It's been known for some time. Some people were 
> using this to run 1 MP and 1 XP to save money on processors. However if you 
> were to update your bios, it might start checking both for being MPs. 
> Original bioses didn't even check for the first processor at one time but AMD 
> complained and the bioses were modified.

I can confirm this. I have two XP 1800 on my A7M266D, and the earlier bioses
reported different CPUs. Now after the bios upgrade, it simply reports that
they both are real MPs ! I even removed the fans once to be sure !

Cheers,
Willy

Re: Dual Athlon CPU detection..

[Thomas Davis]

Mark wrote:
> 
> 
> AFAIK this information comes from the Bios. Some bioses don't verify that the 
> second CPU as being an MP. It's been known for some time. Some people were 
> using this to run 1 MP and 1 XP to save money on processors. However if you 
> were to update your bios, it might start checking both for being MPs. 
> Original bioses didn't even check for the first processor at one time but AMD 
> complained and the bioses were modified.
> 

ah, yes, that's right.

I checked - stupid bios.  Thanks!

thomas