# Very slow hard disk [solved]

## mani001

Hi,

are these results from hdparm normal?

```

cochi tmp $hdparm -tT /dev/sda

/dev/sda:

 Timing cached reads:   1556 MB in  2.00 seconds = 777.46 MB/sec

 Timing buffered disk reads: 284 MB in  3.01 seconds =  94.48 MB/sec

```

My hard disk feels very slow (it didn't always feel like this, of course)...and the PC I use at work performs much better (also according to hdparm):

```

totolaca manu $hdparm -tT /dev/sda

/dev/sda:

 Timing cached reads:   10748 MB in  2.00 seconds = 5379.36 MB/sec

 Timing buffered disk reads: 370 MB in  3.01 seconds = 122.81 MB/sec

```

Is there some parameter I don't know of that can have such an impact on the performance?

The info that hdparm returns is

```

cochi tmp $hdparm -i /dev/sda

/dev/sda:

 Model=ST3500320AS, FwRev=SD1A, SerialNo=9QM13T7L

 Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs RotSpdTol>.5% }

 RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=4

 BuffType=unknown, BuffSize=unknown, MaxMultSect=16, MultSect=16

 CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=976773168

 IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}

 PIO modes:  pio0 pio1 pio2 pio3 pio4 

 DMA modes:  mdma0 mdma1 mdma2 

 UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5 *udma6 

 AdvancedPM=no WriteCache=enabled

 Drive conforms to: unknown:  ATA/ATAPI-4,5,6,7

 * signifies the current active mode

```

Cheers!!Last edited by mani001 on Sat May 05, 2012 5:46 pm; edited 1 time in total

----------

## Hu

Can you provide the output of smartctl -a /dev/sda from both machines?  If you do not have smartctl, you must first emerge sys-apps/smartmontools.

----------

## mani001

I checked that before and I couldn't see any "FAILING" attributes...but anyway I'm not much of an expert on hard disks, so there they go... For the machine that I've got at home (the one with the issue)

```

root@manu $smartctl -a /dev/sda                                                                      

smartctl 5.42 2011-10-20 r3458 [x86_64-linux-3.2.12-gentoo] (local build)                                  

Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net                                 

                                                                                                           

=== START OF INFORMATION SECTION ===                                                                       

Model Family:     Seagate Barracuda 7200.11                                                                

Device Model:     ST3500320AS                                                                              

Serial Number:    9QM13T7L                                                                                 

LU WWN Device Id: 5 000c50 009be7f55                                                                       

Firmware Version: SD1A                                                                                     

User Capacity:    500,107,862,016 bytes [500 GB]                                                           

Sector Size:      512 bytes logical/physical                                                               

Device is:        In smartctl database [for details use: -P show]                                          

ATA Version is:   8

ATA Standard is:  ATA-8-ACS revision 4

Local Time is:    Thu May  3 16:14:46 2012 CEST

SMART support is: Available - device has SMART capability.

SMART support is: Enabled

=== START OF READ SMART DATA SECTION ===

SMART overall-health self-assessment test result: PASSED

General SMART Values:

Offline data collection status:  (0x82) Offline data collection activity

                                        was completed without error.

                                        Auto Offline Data Collection: Enabled.

Self-test execution status:      (   0) The previous self-test routine completed

                                        without error or no self-test has ever 

                                        been run.

Total time to complete Offline 

data collection:                (  625) seconds.

Offline data collection

capabilities:                    (0x7b) SMART execute Offline immediate.

                                        Auto Offline data collection on/off support.

                                        Suspend Offline collection upon new

                                        command.

                                        Offline surface scan supported.

                                        Self-test supported.

                                        Conveyance Self-test supported.

                                        Selective Self-test supported.

SMART capabilities:            (0x0003) Saves SMART data before entering

                                        power-saving mode.

                                        Supports SMART auto save timer.

Error logging capability:        (0x01) Error logging supported.

                                        General Purpose Logging supported.

Short self-test routine 

recommended polling time:        (   1) minutes.

Extended self-test routine

recommended polling time:        ( 112) minutes.

Conveyance self-test routine

recommended polling time:        (   2) minutes.

SCT capabilities:              (0x103b) SCT Status supported.

                                        SCT Error Recovery Control supported.

                                        SCT Feature Control supported.

                                        SCT Data Table supported.

SMART Attributes Data Structure revision number: 10

Vendor Specific SMART Attributes with Thresholds:

ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE

  1 Raw_Read_Error_Rate     0x000f   119   099   006    Pre-fail  Always       -       234257312

  3 Spin_Up_Time            0x0003   095   091   000    Pre-fail  Always       -       0

  4 Start_Stop_Count        0x0032   098   098   020    Old_age   Always       -       2577

  5 Reallocated_Sector_Ct   0x0033   100   100   036    Pre-fail  Always       -       0

  7 Seek_Error_Rate         0x000f   041   039   030    Pre-fail  Always       -       47601253690776

  9 Power_On_Hours          0x0032   085   085   000    Old_age   Always       -       13288

 10 Spin_Retry_Count        0x0013   100   100   097    Pre-fail  Always       -       130

 12 Power_Cycle_Count       0x0032   098   037   020    Old_age   Always       -       2328

184 End-to-End_Error        0x0032   100   100   099    Old_age   Always       -       0

187 Reported_Uncorrect      0x0032   100   100   000    Old_age   Always       -       0

188 Command_Timeout         0x0032   100   086   000    Old_age   Always       -       8590068280

189 High_Fly_Writes         0x003a   100   100   000    Old_age   Always       -       0

190 Airflow_Temperature_Cel 0x0022   065   057   045    Old_age   Always       -       35 (Min/Max 22/35)

194 Temperature_Celsius     0x0022   035   043   000    Old_age   Always       -       35 (0 14 0 0 0)

195 Hardware_ECC_Recovered  0x001a   042   021   000    Old_age   Always       -       234257312

197 Current_Pending_Sector  0x0012   100   100   000    Old_age   Always       -       0

198 Offline_Uncorrectable   0x0010   100   100   000    Old_age   Offline      -       0

199 UDMA_CRC_Error_Count    0x003e   200   200   000    Old_age   Always       -       2

SMART Error Log Version: 1

No Errors Logged

SMART Self-test log structure revision number 1

Num  Test_Description    Status                  Remaining  LifeTime(hours)  LBA_of_first_error

# 1  Extended offline    Completed without error       00%     13255         -

# 2  Extended offline    Completed without error       00%     13191         -

# 3  Extended offline    Completed without error       00%     13142         -

# 4  Extended offline    Completed without error       00%     13081         -

# 5  Extended offline    Completed without error       00%     12975         -

# 6  Extended offline    Aborted by host               90%     12974         -

# 7  Extended offline    Completed without error       00%     12905         -

# 8  Extended offline    Interrupted (host reset)      00%     12838         -

# 9  Extended offline    Completed without error       00%     12774         -

#10  Extended offline    Completed without error       00%     12647         -

#11  Extended offline    Completed without error       00%     12566         -

#12  Extended offline    Completed without error       00%     12474         -

#13  Extended offline    Completed without error       00%     12371         -

#14  Extended offline    Completed without error       00%     12257         -

#15  Extended offline    Interrupted (host reset)      90%     12152         -

#16  Extended offline    Interrupted (host reset)      00%     12048         -

#17  Extended offline    Interrupted (host reset)      00%     11935         -

#18  Extended offline    Interrupted (host reset)      00%     11829         -

#19  Extended offline    Completed without error       00%     11768         -

#20  Extended offline    Interrupted (host reset)      00%     11685         -

#21  Extended offline    Interrupted (host reset)      00%     11571         -

SMART Selective self-test log data structure revision number 1

 SPAN  MIN_LBA  MAX_LBA  CURRENT_TEST_STATUS

    1        0        0  Not_testing

    2        0        0  Not_testing

    3        0        0  Not_testing

    4        0        0  Not_testing

    5        0        0  Not_testing

Selective self-test flags (0x0):

  After scanning selected spans, do NOT read-scan remainder of disk.

If Selective self-test is pending on power-up, resume after 0 minute delay.

```

For my workstation:

```

root@manu $smartctl -a /dev/sda

smartctl 5.42 2011-10-20 r3458 [x86_64-linux-3.2.1-gentoo-r2] (local build)

Copyright (C) 2002-11 by Bruce Allen, http://smartmontools.sourceforge.net

=== START OF INFORMATION SECTION ===

Model Family:     Seagate Barracuda 7200.12

Device Model:     ST3500418AS

Serial Number:    9VMBJCGC

LU WWN Device Id: 5 000c50 02222c6f9

Firmware Version: CC38

User Capacity:    500,107,862,016 bytes [500 GB]

Sector Size:      512 bytes logical/physical

Device is:        In smartctl database [for details use: -P show]

ATA Version is:   8

ATA Standard is:  ATA-8-ACS revision 4

Local Time is:    Thu May  3 16:18:35 2012 CEST

SMART support is: Available - device has SMART capability.

SMART support is: Enabled

=== START OF READ SMART DATA SECTION ===

SMART overall-health self-assessment test result: PASSED

General SMART Values:

Offline data collection status:  (0x82) Offline data collection activity

                                        was completed without error.

                                        Auto Offline Data Collection: Enabled.

Self-test execution status:      (   0) The previous self-test routine completed

                                        without error or no self-test has ever 

                                        been run.

Total time to complete Offline 

data collection:                (  600) seconds.

Offline data collection

capabilities:                    (0x7b) SMART execute Offline immediate.

                                        Auto Offline data collection on/off support.

                                        Suspend Offline collection upon new

                                        command.

                                        Offline surface scan supported.

                                        Self-test supported.

                                        Conveyance Self-test supported.

                                        Selective Self-test supported.

SMART capabilities:            (0x0003) Saves SMART data before entering

                                        power-saving mode.

                                        Supports SMART auto save timer.

Error logging capability:        (0x01) Error logging supported.

                                        General Purpose Logging supported.

Short self-test routine 

recommended polling time:        (   1) minutes.

Extended self-test routine

recommended polling time:        (  88) minutes.

Conveyance self-test routine

recommended polling time:        (   2) minutes.

SCT capabilities:              (0x103f) SCT Status supported.

                                        SCT Error Recovery Control supported.

                                        SCT Feature Control supported.

                                        SCT Data Table supported.

SMART Attributes Data Structure revision number: 10

Vendor Specific SMART Attributes with Thresholds:

ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE

  1 Raw_Read_Error_Rate     0x000f   106   099   006    Pre-fail  Always       -       10559715

  3 Spin_Up_Time            0x0003   097   097   000    Pre-fail  Always       -       0

  4 Start_Stop_Count        0x0032   100   100   020    Old_age   Always       -       222

  5 Reallocated_Sector_Ct   0x0033   100   100   036    Pre-fail  Always       -       0

  7 Seek_Error_Rate         0x000f   081   060   030    Pre-fail  Always       -       130648122

  9 Power_On_Hours          0x0032   082   082   000    Old_age   Always       -       15940

 10 Spin_Retry_Count        0x0013   100   100   097    Pre-fail  Always       -       0

 12 Power_Cycle_Count       0x0032   100   100   020    Old_age   Always       -       111

183 Runtime_Bad_Block       0x0032   100   100   000    Old_age   Always       -       0

184 End-to-End_Error        0x0032   100   100   099    Old_age   Always       -       0

187 Reported_Uncorrect      0x0032   100   100   000    Old_age   Always       -       0

188 Command_Timeout         0x0032   100   096   000    Old_age   Always       -       339

189 High_Fly_Writes         0x003a   100   100   000    Old_age   Always       -       0

190 Airflow_Temperature_Cel 0x0022   068   058   045    Old_age   Always       -       32 (Min/Max 25/39)

194 Temperature_Celsius     0x0022   032   042   000    Old_age   Always       -       32 (0 18 0 0 0)

195 Hardware_ECC_Recovered  0x001a   037   024   000    Old_age   Always       -       10559715

197 Current_Pending_Sector  0x0012   100   100   000    Old_age   Always       -       0

198 Offline_Uncorrectable   0x0010   100   100   000    Old_age   Offline      -       0

199 UDMA_CRC_Error_Count    0x003e   200   200   000    Old_age   Always       -       0

240 Head_Flying_Hours       0x0000   100   253   000    Old_age   Offline      -       24008867200879

241 Total_LBAs_Written      0x0000   100   253   000    Old_age   Offline      -       586131309

242 Total_LBAs_Read         0x0000   100   253   000    Old_age   Offline      -       2414414507

SMART Error Log Version: 1

No Errors Logged

SMART Self-test log structure revision number 1

Num  Test_Description    Status                  Remaining  LifeTime(hours)  LBA_of_first_error

# 1  Extended offline    Completed without error       00%     15642         -

# 2  Extended offline    Completed without error       00%     15474         -

# 3  Extended offline    Completed without error       00%     15306         -

# 4  Extended offline    Completed without error       00%     15138         -

# 5  Extended offline    Completed without error       00%     14971         -

# 6  Extended offline    Completed without error       00%     14803         -

# 7  Extended offline    Completed without error       00%     14635         -

# 8  Extended offline    Completed without error       00%     14467         -

# 9  Extended offline    Completed without error       00%     14299         -

#10  Extended offline    Completed without error       00%     14130         -

#11  Extended offline    Completed without error       00%     13962         -

#12  Extended offline    Completed without error       00%     13794         -

#13  Extended offline    Completed without error       00%     13626         -

#14  Extended offline    Completed without error       00%     13458         -

#15  Extended offline    Completed without error       00%     13290         -

#16  Extended offline    Completed without error       00%     13122         -

#17  Extended offline    Completed without error       00%     12954         -

#18  Extended offline    Completed without error       00%     12786         -

#19  Extended offline    Completed without error       00%     12619         -

#20  Extended offline    Completed without error       00%     12450         -

#21  Extended offline    Completed without error       00%     12282         -

SMART Selective self-test log data structure revision number 1

 SPAN  MIN_LBA  MAX_LBA  CURRENT_TEST_STATUS

    1        0        0  Not_testing

    2        0        0  Not_testing

    3        0        0  Not_testing

    4        0        0  Not_testing

    5        0        0  Not_testing

Selective self-test flags (0x0):

  After scanning selected spans, do NOT read-scan remainder of disk.

If Selective self-test is pending on power-up, resume after 0 minute delay.

```

A funny thing is my home computer has another much newer hard disk and it's equally slow...That's why I think there might be something wrong with my setup or some subtle kernel tweak I don't know about...   :Confused: 

----------

## DirtyHairy

Your harddrive speed is represented by the "buffered disk reads",and I would call that value completely normal for a reasonably modern SATA drive. The "cached reads" does not involve any actual disk access and is a measure of how fast the kernel will serve cached data and is more a measure of your memory speed than anything else. The value actually _is_ pretty low. What kind of system are you measuring? For your reference, the readings from my laptop (thinkpad T420) are

```
 Timing cached reads:   14078 MB in  2.00 seconds = 7043.55 MB/sec

 Timing buffered disk reads: 298 MB in  3.00 seconds =  99.32 MB/sec
```

----------

## i92guboj

 *mani001 wrote:*   

> Hi,
> 
> are these results from hdparm normal?
> 
> ```
> ...

 

These values are reasonable for SATA hardware. The thing you need to care about is the buffered disk read, and those are moving around the same magnitude (and, again, the values are reasonable for a SATA drive).

The cached reads do not say anything about your disk, and are influenced by a number of factors that have nothing to do with the disk (and some others that do not even have to do with your hardware at any level).

 *Quote:*   

> Is there some parameter I don't know of that can have such an impact on the performance?

 

Your kernel version, fs driver, the kind and number of files you are reading, your i/o scheduler, and many others can influence your overall performance in which regards disk i/o. Greatly. But there's not much you can tweak yourself these days besides making sure you are not using some krrazy kernel patchset, and besides making sure you are using the latest stable kernel from either upstream or Gentoo. Overall if you use a young fs such as ext4.

Also, note that hdparm is intended mostly for IDE/ATA drives, so, besides testing the disk speed, this tool is not suitable for SATA drives.

If you feel your system lags in some way, you will have to better identify your problem and look elsewhere.

----------

## mani001

Ok, then, you convinced me  :Smile:  the hard disk is probably not to blame, but anyway this is kind of weird...and annoying   :Confused: 

About my system: It's a Pentium Dual 2.5 GHz with 4GB's of memory (quite an old machine, indeed, but that shoudn't matter...should it?). Also, I'm running on a 3.2.12-gentoo kernel and my filesystem is ext4. 

To be honest, I'm at my wits end, but If I solve this issue I will get back and post the solution...Anyway, thank you very much for your suggestions!!

----------

## i92guboj

 *mani001 wrote:*   

> Ok, then, you convinced me  the hard disk is probably not to blame, but anyway this is kind of weird...and annoying  
> 
> About my system: It's a Pentium Dual 2.5 GHz with 4GB's of memory (quite an old machine, indeed, but that shoudn't matter...should it?). Also, I'm running on a 3.2.12-gentoo kernel and my filesystem is ext4. 
> 
> To be honest, I'm at my wits end, but If I solve this issue I will get back and post the solution...Anyway, thank you very much for your suggestions!!

 

I think that you've got the wrong impression that the difference in the values from one machine to the other is significative, and the fact is that it is not. It's that low that could very well be bound to the different cpu's or, much probably, to a better mother board where the dma and the SATA bus is just working the way it should, unlike in most cheap motherboards, and some of them that are not that cheap.

In any case, it is to be expected that a pentium 4 board will use an inferior sata standard, and in consequence, the same disk will perform worse in that board than in a modern board using a higher sata standard.

If your system is lagging in a concrete way (e.g. long time to boot, long time to start applications, it's irresponsive while you do a concrete task, it takes long to do something that you think should take less time....) create a new thread, and expose the symptoms you are experiencing. Don't assume a diagnostic unless you are sure about what you are saying, because that can misslead people that's trying to help you.

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## mani001

Yes, I got that "wrong" impression because 5 times faster "Timing cached reads" in one machine looks significant to me... I don't know to which extent the motherboard can have such an impact on the performance, but anyway I woudn't say mine is a cheap low-quality one http://www.msi.com/product/mb/P6NGM-FIH.html (I chose it myself). Furthermore, I don't think hard disks, motherboards, dma controllers or whatever have improved that much in a few years (unfortunately...).

I think the hard disk is the problem because of that and because right after logging into kde (when, seemingly, everything has been loaded), I can hear the hard disk and see the LED blinking for what it feels like a lot of time (maybe 8-10 seconds). I know that KDE uses a lot of resources, specially the nepomuk stuff, but even so it's kind of weird...

Of course, I could be totally wrong and this might have nothing to do with the hard disk and be related to something else as you say...but everything points at it   :Rolling Eyes:  Right now, I'm trying enabling and disabling some kernel options to see if I get some performance boost.

Cheers!!

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## i92guboj

 *mani001 wrote:*   

> Yes, I got that "wrong" impression because 5 times faster "Timing cached reads" in one machine looks significant to me... I don't know to which extent the motherboard can have such an impact on the performance, but anyway I woudn't say mine is a cheap low-quality one http://www.msi.com/product/mb/P6NGM-FIH.html (I chose it myself). Furthermore, I don't think hard disks, motherboards, dma controllers or whatever have improved that much in a few years (unfortunately...).
> 
> 

 

You insist in comparing cached reads as if that could tell anything realistic about the real speed of your hard disk. That number probably tells you more about the caching predictions technology in your cpu and the ram speed than about your hd.

 *Quote:*   

> I think the hard disk is the problem because of that and because right after logging into kde (when, seemingly, everything has been loaded), I can hear the hard disk and see the LED blinking for what it feels like a lot of time (maybe 8-10 seconds). I know that KDE uses a lot of resources, specially the nepomuk stuff, but even so it's kind of weird...

 

If you think that eight seconds after starting kde is too much for nepomuk, you are a lucky nepomuk user, I swear. In any case, isn't it logical to think that, if the problem arises only in kde, maybe it's a kde problem?

For me, the performance in kde is "acceptable" nowadays, but not "great". It feels slow and heavy, menus take long to fire up and programs take long to open, when compared to other environments. Disabling the compositing (desktop effects) increases the performance by a noticeable amount for me. But it's still sub-par.

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## eccerr0r

Also make sure your hdparm versions match though this shouldn't be an issue as of late.

The cached disk reads, though it is a benchmark of CPU speeds, does exercise the bus a bit.  How the bus and chipset are designed.

This is from my C2D E6700 (G965/SATA) 64-bit Linux

 Timing cached reads:   6904 MB in  2.00 seconds = 3454.42 MB/sec

 Timing buffered disk reads: 174 MB in  3.00 seconds =  57.97 MB/sec

This is from my C2Q Q9550 (P43/SATA)

 Timing cached reads:   13368 MB in  2.00 seconds = 6700.63 MB/sec

 Timing buffered disk reads: 224 MB in  3.03 seconds =  74.04 MB/sec

This is from my Athlon XP 2200+ (SiS735/PATA)

 Timing cached reads:   490 MB in  2.01 seconds = 244.38 MB/sec

 Timing buffered disk reads: 174 MB in  3.01 seconds =  57.83 MB/sec

This is from my i7 2700K (Z68/SATA/SSD)

 Timing cached reads:   29206 MB in  2.00 seconds = 14624.82 MB/sec

 Timing buffered disk reads: 1128 MB in  3.00 seconds = 375.98 MB/sec

This is from my Celeron-M 1.5GHz (915/PATA).  This one the disk speed is broken, but cached speeds is OK.

 Timing cached reads:   1068 MB in  2.00 seconds = 534.10 MB/sec

 Timing buffered disk reads: 132 MB in  3.09 seconds =  10.35 MB/sec

This is from my P4 Model 650 (i865/SATA)  64 bit Linux.  Incidently, this motherboard was also made by MSI

 Timing cached reads:   2092 MB in  2.00 seconds = 1045.53 MB/sec

 Timing buffered disk reads: 176 MB in  3.03 seconds =  58.06 MB/sec

As you can see yes there is a strong correlation of cached reads and CPU speeds, but comparing the Athlon and the Celeron-M you can see a huge discrepancy despite the Athlon being at least somewhat comparable to the Celeron-M.  I sort of attribute it to the chipset; though SiS tends to make OK chipsets, I readily despise Via chipsets as they are really slow.  I don't know enough about Nvidia's designs, I've never tried their chipsets before.

But in any case, these numbers are only one piece of system performance,   I think you may be comparing machines that are considerably different from each other, probably different chipsets as well.

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## mani001

mmm...I think you're both (eccerr0r and i92guboj) right   :Embarassed:  I should have RTFM before posting. From hdparm manual, about -T option

 *Quote:*   

> 
> 
> This measurement is essentially an indication of the throughput of the processor, cache, and memory of the system under test.
> 
> 

 

So, the performance I get from hdparm is what it is (utter crap   :Confused:   ) but it must be due to the old hardware (everything but the hard disk, probably    :Very Happy:   )

 *Quote:*   

> 
> 
>  isn't it logical to think that, if the problem arises only in kde, maybe it's a kde problem?
> 
> 

 

well, yes, but I didn't think that the problem was arising only in KDE, I just thought I noticed in KDE because KDE was heavily using the hard disk at startup. Then, I thought I needed an additional (more objective) hard disk performance test...and it was then when I tried hdparm and noticed the low "Timing cached reads"...after that I got paranoid and you know the rest   :Very Happy: 

eccerr0r, indeed I was comparing two different systems (dual core against core i7   :Rolling Eyes:   )

I alse came up with the idea of trying the same thing in Windows...but it seems there is no hdparm for Windows and it doesn't work that well through cygwin.

Sooo, thank you very much for your help...and sorry to have been bothering about this... I'm adding "solved" to the subject.

Cheers!!

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## eccerr0r

Yeah, my i7 is blowing even my c2q out of the water, mostly due to the QPI and DDR3-1333 I presume.  I can't really tell you why my C2D and C2Q are so far apart though... the C2Q is using DDR2-800 versus the DDR2-533 on the C2D, plus the fact that one's using a 32-bit and the other's a 64-bit install, making a non apples-to-apples comparison.  I doubt that hdparm -T is optimized for anything so the test really is meaningless, heck, it's a gcc benchmark test too.

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