The Notebook Review forums were hosted by TechTarget, who shut down them down on January 31, 2022. This static read-only archive was pulled by NBR forum users between January 20 and January 31, 2022, in an effort to make sure that the valuable technical information that had been posted on the forums is preserved. For current discussions, many NBR forum users moved over to NotebookTalk.net after the shutdown.
Problems? See this thread at archive.org.

    Lowest Clock Speed of 1066 MHz FSB Penryn

    Discussion in 'Hardware Components and Aftermarket Upgrades' started by admlam, Sep 30, 2008.

  1. admlam

    admlam Notebook Deity NBR Reviewer

    Reputations:
    221
    Messages:
    1,203
    Likes Received:
    0
    Trophy Points:
    55
    Hi,

    Just wondering if we could get a feel for the lowest clock speed for various Penryn processors on battery.

    My P7350 comes in at 1.6GHz, which seems high compared to the 800MHz on my brother's Merom T5270.
     
    admlam, Sep 30, 2008
    #1
  2. Andy

    Andy Notebook Prophet

    Reputations:
    2,133
    Messages:
    6,399
    Likes Received:
    1
    Trophy Points:
    206
    Lowest multiplier in almost all Intel mobile CPUs is 6x. They assign a common min multipler, mainly due to stability issues, and they can't go on testing each CPU for the min. voltage and multiplier.

    The BUS Speed is alot higher now: 266MHz vs 200MHz.

    P7350: 6*266 = 1596
    T5270: 6*200 = 1200

    Now the even lower clocks are attained due to features such as SuperLFM, which I think were available starting from the T7xxx, which drop the Bus Speed down to 133MHz. (133*6 = 800)
     
    Andy, Sep 30, 2008
    #2
  3. admlam

    admlam Notebook Deity NBR Reviewer

    Reputations:
    221
    Messages:
    1,203
    Likes Received:
    0
    Trophy Points:
    55
    Thanks for the explanation.

    So SuperLFM is a feature exclusive to RMClock?
     
    admlam, Sep 30, 2008
    #3
  4. IntelUser

    IntelUser Notebook Deity

    Reputations:
    364
    Messages:
    1,642
    Likes Received:
    75
    Trophy Points:
    66
    SuperLFM feature exists in ALL Core 2 Duo based notebooks that are Santa Rosa and later. SuperLFM simply put, is a feature that puts the FSB at half the clock of what it is normal to reduce CPU core clock speed.
     
    IntelUser, Sep 30, 2008
    #4
  5. Andy

    Andy Notebook Prophet

    Reputations:
    2,133
    Messages:
    6,399
    Likes Received:
    1
    Trophy Points:
    206
    Socket P processors are capable of throttling the FSB anywhere between 400-800 MHz as necessary.
     
    Andy, Sep 30, 2008
    #5
  6. John Ratsey

    John Ratsey Moderately inquisitive Super Moderator

    Reputations:
    7,197
    Messages:
    28,841
    Likes Received:
    2,166
    Trophy Points:
    581
    CPU-Z newer than about V1.42 doesn't seem to see the SLFM mode.

    I have the old 1.40.5 and this reports the full load speed properly and says 800MHz when idle. V1.47 says 1.60GHz for the same idle condition.

    John
     
    John Ratsey, Sep 30, 2008
    #6