Imac 27" and PS3 - you can change screen settings to 1080p...

Discussion in 'iMac' started by Andythed, Jan 13, 2011.

  1. Andythed macrumors member

    Jan 13, 2011

    I am new to the forum, however I visit it regularly.

    I recently bought the 27" iMac to use as a all in one ,tv, hifi,etc

    I have followed the PS3/Xbox connection threads with interest as I too would like to hook up a PS3 with 1080p input...

    As I understand it the iMac will not take 1080p.

    You can change your screen settings to 1080p. So, with this option selected, shouldn't the 1080p signal from a PS3 be able to work easily? Screen is then 1080p...input is 1080p......

    From what I know this doesn't work..but why?

    I am pretty sure I am missing some understanding as to why this is not true. So I thought I would ask if someone can explain this to me?


  2. Hellhammer Moderator


    Staff Member

    Dec 10, 2008
    The issue is not the screen, it's something between the PS3 and the display. IIRC it is Apple's limitation in the firmware, they could make it 1080p if they wanted.
  3. Andythed thread starter macrumors member

    Jan 13, 2011
    Thanks for the reply

    I was confused. Because by changing the screen settings to 1080p, surely the imac is displaying 1080p on a 1440p screen? And easily?

    But by judging from your reply its not whether the iMac can do it, its that Apple wont allow it.

    I had read posts stating that 1080p input would require extra hardware in the mac.

    I think I may be trying to be clever beyond my brains capabilities in understanding the details of it.
  4. Hellhammer Moderator


    Staff Member

    Dec 10, 2008
  5. Danando1993 macrumors regular

    Aug 14, 2010
    Its frustrating not being able to use my ps3 with 1080p but i just decided to order a kanex xd instead. somethings better than nothing
  6. Andythed thread starter macrumors member

    Jan 13, 2011
    How has the Kanex worked out for you? Thats what I am thinking of getting.

    Apparently on a screen the size of the imac 720p or 1080p on doesn't really matter. How does it compare to a full HD tv?
  7. Wang Foolio macrumors regular

    Jan 11, 2010
    The screen in OSX can display a large number of resolutions obviously. The mini display port doesn't support 1080p signals coming in, however. It prefers the 720p or 1440p. If you want the full 1080p signal (obviously only an issue for menus and Blu Ray at the moment as most games are 720p tops for either 360 or PS3) then you have to get a scaler that will boost a 1080p signal to 1440p. Without this, your input signal remains capped at 720p as this is the highest resolution you'll be getting over plain HDMI.

    Yes, it kinda sucks. There are times when I want to explore this option to get gaming in me bedroom (as opposed to just the living room) but then I remind myself that my iMac wouldn't be giving me 5.1 surround anyway without adding major investments like a second AVR, so there's not much point. Playing Starcraft and stuff is fine in stereo, but CoD etc. would be a big step backwards. After I got used to 5.1 with my old PC, Astro A40's and obviously my home theatre, I can't really go back :p

    Anyway I don't really think the iMac is the ultimate all in one, it can be good enough if you're really stuck for space in your home, but even with the higher resolution panel and all the rest of it, it won't touch a real home theatre setup. I am curious how you managed to set it all up for use as a computer and for comfortably watching movies. Was it a bedroom arrangement?
  8. lilB, Jan 14, 2011
    Last edited: Jan 14, 2011

    lilB macrumors newbie

    Jan 14, 2011
    Not exactly. iMacs are like laptops, so the graphics card controls the LCD directly via LVDS. There is no scaling hardware inside the iMac. All scaling is done via software. The GPU will always output native resolution no matter what resolution you select in OSX.

    The GPU can't accept displayport signals because of HDCP, so the signal has to be converted directly and you can't use the GPU for scaling with an external device.

    HDMI devices can't output at the native resolution of the iMac, with direct conversion it can only work at 50% resolution, essentially doubling the pixels. (720p)

    If you add an external scaler (or a HDMI to DP converter with one built in), you can then run it at 1080P.

    A high quality external scaler connected to an iMac would probably give better image quality than comparable consumer displays with a native resolution higher than 1080p, since most consumer displays have very poor scaling hardware.

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