Will 4gb of ram make the MBP faster in any case?

Discussion in 'MacBook Pro' started by picchiant, Aug 13, 2007.

  1. picchiant macrumors newbie


    Aug 1, 2007
    Hello people, I've just got a MBP with 2gb of ram. I would like to upgrade the ram to 4gb, unfortunatly seems that all the 2gb sodimm modules have a CL5 instead of CL4 as the 1gb sodimm modules... So I am wondering if this bigger Latency (cl5) will slow down the MBP for non hungry memory processes.
    4gb of ram will make the MBP faster in any case? or only when large quantities of emmory are needed...

    thanks for any advice...


  2. mad jew Moderator emeritus

    mad jew

    Apr 3, 2004
    Adelaide, Australia
  3. picchiant thread starter macrumors newbie


    Aug 1, 2007
    thanks but I am wondering more about the latency of 4gb of ram... I know well that doesn;t make the sysmtem faster, I am worrried that eventually it can make the system slower, reducing the speed due the bigger latency.

  4. iBunny macrumors 65816

    Apr 15, 2004
    I found that 4GB of ram has made my computer significantly faster.

    I dont do anything crazy like video edit too, but most of the time, under general usage, im using about 2.5GB of ram. And fluctuates to about 3.5 when using VMWare to run XP.
  5. DaLurker macrumors 6502

    Mar 30, 2006
    CL5 vs CL4 won't make a huge difference in performance, maybe 5%. This is tremendously small performance deficit for the gains you will get from going with more memory.

    In short, don't worry about it!
  6. picchiant thread starter macrumors newbie


    Aug 1, 2007
    IBUNNY, thanks!! this is the sort of answer I was looking for :)

    I've done same research, and seems that a CL4 vs CL5 slows the memory access speed of 1 clock cycle, so if you have a 800mhz bus.... the memory speed will be reduced of 1/800 :)
    the benefit will be to have less paging activity on the disk, so less bottle necks.

  7. maccam macrumors 6502a


    Feb 18, 2007
    Yeah, if you have the money, go for 4 gigs of ram, you will still notice a difference (regardless what CanadaRAM thinks).
  8. picchiant thread starter macrumors newbie


    Aug 1, 2007
    Hey, I've just installed the 2gb modules!!! to me makes a lot of difference!! boots faster.. .any application starts faster... amazing...

  9. Hobbit6003 macrumors member

    Jun 8, 2007
    Seriously, I've upgraded to 4Gb of RAM on my MBP, and I've not experienced any significant speed boost.

    I'm working with Aperture and Photoshop most of the time.
  10. magius macrumors regular

    Jun 3, 2007
    there is noticeable speed increase if you are working with considerably large media files (whether it be half a gig ps or dv video), plus i have noticed a difference multitasking (whether ps/ai or final cut/ae/motion). working on normal things I doubt you will notice too much of a difference. Same goes with the 5400rpm vs 7200rpm.... though in this case it would probably be even faster to get an external (though an internal 7200 rpm is convinient on the go when you forget/don't want to carry your external).
  11. triddent222 macrumors regular

    Jul 27, 2007
    Somewhere interesting
    lol, i think thats just a placebo effect :p

    "booting" time shouldnt be any different...nor application starting time for that matter. you should only see a difference when working with really big files, or memory hungry applications, in which the ram has to access the HDD less to get the same process accomplished.
  12. CanadaRAM macrumors G5


    Oct 11, 2004
    On the Left Coast - Victoria BC Canada

    1) no major RAM manufacturer is shipping SODIMMs at CL4 at 667 MHz. I know there is one seller of dubious honesty that puts "CL4!!" on their ads. What they don;t say is that it runs CL4 only at 533 MHz. :mad:

    2) The memory bus is 667, not 800. The FSB is 800 but the memory controller is hardware limited to 667 and no amount of more expensive RAM is gonna change that.

    3) there is no additional latency in installing 4 Gb RAM vs 2 Gb RAM
    (this is an issue on the Mac Pro with its FB-DIMMs -- the fifth through eighth FBDIMMs you install have a higher latency than the first 4 because the memory request must pass throough the controller on the first bank of RAM before reaching the second bank.)

    (and the information that CAS Latency slows RAM by one clock cycle is pretty much wrong. IF you had a motherboard AND RAM that fully supported CAS Latency 4 vs CAS Latency 5, there would be a potential 20% gain in memory bandwidth (1/5). However, that does not translate into a 20% improvement in real world performance. Latency would have absolutely no effect on paging)

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