Radeon Pro 450 vs 460 UI fluidness 4k external monitor

Discussion in 'MacBook Pro' started by keviig, Jan 8, 2017.

  1. keviig macrumors 6502

    Jun 7, 2012
    My base model 15" with the 450 has issues with the keyboard, so I'm returning it for a new one.
    While the 450 handles the 4k screen rather well, there are still animation lag and stutter here and there.

    There is a big difference between the Intel 530 iGPU and the 450, so I was thinking even more GPU power could help. I might get a 2nd 4k monitor down the line as well.

    Would I see a noticeable difference by getting the 460 instead?

  2. gordosuperfly macrumors newbie

    Dec 7, 2016
    I would like to know this as well... In my case, will it make using the 5k more fluid? Sometimes with the 450, even expose framerate is jagged... Would 460 speed this up?
  3. aevan macrumors 68030


    Feb 5, 2015

    I don't think it will. However, if someone knows better, I would be interested to know.

    From what I've learned, the only major lag on modern Macs these days is in Mission Control. And this is almost certainly not GPU related. When you see lag, it usually occurs only the first time - repeat the MC animation and the second time it's smooth (if it was GPU related, it would lag then as well). The reason for this lag is pulling the current state of apps or something - and it happens when you have lots of apps open.

    Now, I am unaware of any other lag on Macs - I haven't tried a 4K monitor on my MBP (with Radeon Pro 455) but I doubt there will be any lag, because having the additional screen doesn't mean that the GPU is moving extra 4K pixels at once - you would have to run 2 demanding, full-screen processes on both screens at the same time. I could tell you that adding a 1440p monitor to my iMac 5K or both my MBPs never caused any additional lag (other than the one that was already there - again, Mission Control, especially in Yosemite days)

    Also, think about it - your MBP can run 4.... yes FOUR 4K displays at once. Or two 5K displays at once. I mean, if one display created lag, what would be the case with 4 displays?

    The only way that adding a second display could make the computer lag more is if it had a significantly larger resolution than the one on your MBP, but even that is not possible because if you use the default scaling on a MBP, it is already rendering the image in 3360x2100 (then downsampling it to native panel resolution), and at "More Space" option it is rendering a full 4K image before downsampling it. And it doesn't lag at that resolution. At least mine doesn't.

    Long story short - no, I don't think 460 will make it lag any less with a 4K screen, I think it will be the same. Most of the lag is caused by software. 460 is for GPU demanding stuff like video editing and games, not for UI smoothness. I know a lot of people thinks it is, but, it's not.

    I could be wrong, so if anyone here gives a better explanation, I'll be glad to hear it. (Just don't accept those "There are more pixels so that must mean you need a faster GPU" - because that doesn't really apply).
  4. mcomp112 macrumors regular

    Jan 1, 2017
    Not sure if this helps but my 455 is completely smooth when using a 4K monitor. No experience with 450 or 460 but my 13 inch touch bar with iris 550 graphics stuttered with the same set-up.
  5. pubmsu macrumors regular

    Dec 9, 2014
    Sydney, Australia
    Hi, did you notice any other lag than the Mission Control lag aevan has mentioned? How is desktop switching animation - smooth or stutters?

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