# um.. 800 mhz core 2 duo during compile? - doesn't feel slow

## xanas3712

according to cat /proc/cpuinfo, and sys/devices/cpu/cpu0/ my processor has 2 speeds, 600 mhz, or 800 mhz.  I'm running at 800 when compiling, which doesn't "seem" slow to me (I would use genlop but I decided to rebuild system from scratch) and doesn't seem to be a problem.  Also, still shows then when I was getting 60 consistent fps at 1920x1200 ultra mode in quake 4, so.. it cannot be right.

I'm overclocking just a tad to 333 mhz from 266 on an e6400, so it should be showing 2.6 ghz

Here's my cat /proc/cpuinfo. 

```

processor       : 0

vendor_id       : GenuineIntel

cpu family      : 6

model           : 15

model name      : Intel(R) Core(TM)2 CPU          6400  @ 2.13GHz

stepping        : 6

cpu MHz         : 800.000

cache size      : 2048 KB

physical id     : 0

siblings        : 2

core id         : 0

cpu cores       : 2

fpu             : yes

fpu_exception   : yes

cpuid level     : 10

wp              : yes

flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr lahf_lm

bogomips        : 5331.91

clflush size    : 64

cache_alignment : 64

address sizes   : 36 bits physical, 48 bits virtual

power management:

processor       : 1

vendor_id       : GenuineIntel

cpu family      : 6

model           : 15

model name      : Intel(R) Core(TM)2 CPU          6400  @ 2.13GHz

stepping        : 6

cpu MHz         : 800.000

cache size      : 2048 KB

physical id     : 0

siblings        : 2

core id         : 1

cpu cores       : 2

fpu             : yes

fpu_exception   : yes

cpuid level     : 10

wp              : yes

flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr lahf_lm

bogomips        : 5328.49

clflush size    : 64

cache_alignment : 64

address sizes   : 36 bits physical, 48 bits virtual

power management:

```

Last edited by xanas3712 on Sat Nov 18, 2006 9:59 pm; edited 1 time in total

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## mbjr

Hi,

Your cpuinfo shows 2 800MHz processors, doesn't it?  :Smile: 

Besides "close your eyes and believe", you may try stop overclocking  :Smile: 

Cheers,

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## xanas3712

 *mbjr wrote:*   

> Hi,
> 
> Your cpuinfo shows 2 800MHz processors, doesn't it? 
> 
> Besides "close your eyes and believe", you may try stop overclocking 
> ...

 

It performs better and is perfectly stable at this speed (no crashes whatsoever w/ prime95, 3dmark 05/06, etc.)  so I think I'll stick with it.

I'm just curious why linux seems to be getting the wrong info.  

     Sat Nov 18 15:52:13 2006 >>> kde-base/kdelibs-3.5.5-r7

       merge time: 19 minutes and 30 seconds.

Was my kdelibs compile time.  That doesn't sound abnormally high to me, and I was playing music/browsing during that..

/var/log/messages says this

```

Nov 18 12:52:27 xanas kernel: Booting processor 1/2 APIC 0x1

Nov 18 12:52:27 xanas kernel: time.c: Detected 2664.078 MHz processor.

```

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## mbjr

Well, that time sounds just about right.

I'm stuck with a 3GHz HT for now, but I'm 2 weeks away from getting my e6400 as well, so if no solution turns up till than, I'll be happy to share my experiences.

We'll see if it's kernel - it may be though, e6400 is not one of the oldies.

Cheers,

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## xanas3712

Well I'm not having performance issues, and with this kernel I'm not having the timing issues (I'm using 2.6.19-rc6 due to chipset issues (ICH8/JMicron stuff).  I used the no2 sources kernel and that just had all kinds of problems, time was running about 3-4 times faster than normal, so audio was choppy/fast, etc.

But everything seems good now, games play fine and sound plays fine and compile times seem to be OK.  This is just a glitch in display I think, it doesn't seem to be slowing me down any.. oddness.

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## mbjr

Hi,

Sounds great, hope .19 comes out soon as stable.

Cheers,

----------

## nihilo

As a point of comparison, I'm running a slightly overclocked e6600. The bios says 2700 MHz, and benchmarks indicate that's about right relative to where it started (2.4), but /proc/cpuinfo still says 2.40. I'm using mm-sources 2.6.19_rc5-r2.

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## Computator

I have my FSB set to 333MHz in BIOS and /proc/cpuinfo (correctly) shows the following (still using gentoo-sources 2.6.17-r8 (with all-generic-ide for DVD drive), trying to get X to work with 2.6.18 now):

```
model name      : Intel(R) Core(TM)2 CPU          6600  @ 2.40GHz

cpu MHz         : 2988.090
```

----------

## roadrunner_gs

I have an Intel Xeon 5050 (okay, actually two of them) running on an Asus DSBV-D.

They are reported as "Intel Xeon 3.00GHz" and /proc/cpuinfo as well as /sys/devices/system/cpu/cpu7/cpufreq/scaling_available_frequencies throws out unbelievable values:

cat /sys/devices/system/cpu/cpu7/cpufreq/scaling_available_frequencies

```
7680000 6827000 5973000 5120000
```

cat /proc/cpuinfo

(...)

```
processor       : 7

vendor_id       : GenuineIntel

cpu family      : 15

model           : 6

model name      :                   Intel(R) Xeon(TM) CPU 3.00GHz

stepping        : 4

cpu MHz         : 7680.000

cache size      : 2048 KB

physical id     : 1

siblings        : 4

core id         : 1

cpu cores       : 2

fpu             : yes

fpu_exception   : yes

cpuid level     : 6

wp              : yes

flags           : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est cid cx16 xtpr lahf_lm

bogomips        : 5985.63

clflush size    : 64

cache_alignment : 128

address sizes   : 36 bits physical, 48 bits virtual

power management:
```

/var/log/messages shows that:

```
Nov 28 01:37:00 poetsrv02 time.c: Detected 2992.593 MHz processor.
```

What is going on, eh?

How could i know the CPUs are running at full speed now?

Should i update the BIOS to the newest availlable?

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## kruthles

I am also seeing an incorrect speed displayed.

in my case it seems that the linux kernel I am currently using (2.6.19) uses the stock multiplier for processor frequency calculations regardless of what you actually have the multiplier set to.

My current setup is a e6600 running at 425*8 with a bios reported speed of 3400mhz

/proc/cpuinfo incorrectly lists the speed as 3825mhz.

The e6600 has a default multiplier of 9 and 9*425 = 3825mhz.

Enhanced Speed Step is Disabled in my kernel.

Update:

/var/log/messages reports the following on my system, for me the detected speed is incorrect.

```
Jan 18 21:14:13 core Detected 26.562 MHz APIC timer.

Jan 18 21:14:13 core time.c: Using 25.000000 MHz WALL HPET GTOD HPET/TSC timer.

Jan 18 21:14:13 core time.c: Detected 3825.012 MHz processor.

```

Last edited by kruthles on Fri Jan 19, 2007 3:24 am; edited 1 time in total

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## nihilo

 *kruthles wrote:*   

> I am also seeing an incorrect speed displayed.
> 
> Enhanced Speed Step is Disabled in my kernel.

 

How come you have Enhanced Speed Step disabled? Just curious, because I'm having issues with the wrong time being reported, but I have Enhanced Speed Step enabled and scaling seems correct (just the values are reported incorrectly, using the default multiplier rather than the higher than default multiplier).

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## rmh3093

cpu cache mem is more important than clock speed when compiling.... thats why it doesnt feel slow... the core2duo has 4mb which is huge

when compiling openoffice the time difference between a 2ghz p4 w/ 512k and a 2ghz p4 based celeron w/ 128k is in the magnitude of hours

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## kruthles

 *nihilo wrote:*   

>  *kruthles wrote:*   I am also seeing an incorrect speed displayed.
> 
> Enhanced Speed Step is Disabled in my kernel. 
> 
> How come you have Enhanced Speed Step disabled? Just curious, because I'm having issues with the wrong time being reported, but I have Enhanced Speed Step enabled and scaling seems correct (just the values are reported incorrectly, using the default multiplier rather than the higher than default multiplier).

 

The system is so new I simply have not had much time to test it...

 :Wink: 

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## obrut<-

forget about the clock /proc/cpuinfo reports to you. it's obviously wrong. the bogo mips are a good indicator for the real clock instead. devide this number by 2 and you have your clock speed in mhz.

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## kruthles

 *obrut<- wrote:*   

> forget about the clock /proc/cpuinfo reports to you. it's obviously wrong. the bogo mips are a good indicator for the real clock instead. devide this number by 2 and you have your clock speed in mhz.

 

I am trying to find the reason why the clock speed is reported incorrectly, I am well aware that the reported value is incorrect...

fyi: on my system bogomips is reported as.

```
bogomips        : 7650.11
```

bogomips divided by 2 here still gives me the incorrect speed (7650 / 2 = 3825).

the true cpu speed reported by the bios is still 3400Mhz

----------

## nihilo

 *obrut<- wrote:*   

> forget about the clock /proc/cpuinfo reports to you. it's obviously wrong. the bogo mips are a good indicator for the real clock instead. devide this number by 2 and you have your clock speed in mhz.

 

Confirming that this is true for me. I'm overclocked to 2.7 GHz (rather than 2.4), and my BogoMIPS are "5399.48 BogoMIPS". So /proc/cpuinfo is incorrect for me, as is the gnome cpu applet, but BogoMIPS is reported correctly.

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## olger901

Try to totally disable Speedstep and any other CPU limiting technology in your BIOS and the Kernel.

----------

