Choppy Graphics on iMac Early '08 in Lion

Discussion in 'iMac' started by ninjaslim, Aug 12, 2011.

  1. ninjaslim macrumors member

    Jul 27, 2010
    I have an early '08 iMac with a Core 2 Duo 2.4 Ghz and an ATi Radeon 2400 XT 128MB. It also has 2 GB of RAM. Everything has worked better than Leopard and Snow Leopard except the graphics, which are extremely choppy, especially the animations for Mission Control and Launchpad. Could anyone please give some advice as to what's going on?

  2. Spike88 macrumors 6502a

    Jan 25, 2010
    When your graphics in running choppy, can you hold those apps in the background, then start Activity Monitor. Then, share screen print pictures of its CPU, Memory, Hard Disk and Network pages. Seeing the details in these sheets will help us investigate (and recommend solutions).

  3. ninjaslim thread starter macrumors member

    Jul 27, 2010
    I have attached the relevant screenshots to this post.

    Attached Files:

  4. Spike88, Aug 13, 2011
    Last edited: Aug 15, 2011

    Spike88 macrumors 6502a

    Jan 25, 2010
    Looking at your Hard Disk usage graph, you'll notice a huge spike of activity (to the top of the graph). Looking at your System Memory graph, I see lots of page-ins, and page-outs as well. And, I see Free memory is under 500 MB. As an unwritten rule, free memory should be consistantly more than 500 MB (or its starving for more physical ram). I also see very few processes on the CPU. Thus, showing CPU is not being congested.

    With these items in mind (without going into unversity level explanations and industry standard of less then 10% paging ratios), I'd say your iMac system needs more physical memory. Since memory is very "inexpensive" these days, I would simply buy / install more memory. As much physical memory as your iMac model can take. Is that 4 GBs??? Not too sure. With more physical memory, your iMac would perform less "disk thrashing". re: Paging in/out because it's run out of memory. And, becuase the CPU must page out/in, some of its power is being used for disk activity - instead of processing the applicaton. Thus, negative impact on CPU, even though its not shown on its CPU chart.

    Form more details about disk thrashing, surf:

    Long mumblings short... I would install more physical memory (4 GBs) and compare performance again. Since memory is inexpensive these days, I'd buy it now. Especially if you plan to keep your existing iMac.

    Note: If I remember correctly, Lion recommends a minimum 2 GBs of memory. As more and more applications are added, the need for more memory increases. As an unwritten rule (based on my experience), I take the OS "minimum" recommendation and double it. In other words, Lion really needs minimum 4 GBs of physical memory - for "acceptable" performance for the average home user.

    Hope this helps in your research....

Share This Page