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macrumors 6502a
Original poster
Mar 26, 2012
Since there's been a lot of talk about the 5k 27 inch iMac and the gpu requirements to run that kind of display efficiently, I was curious what is needed to run scaled 4k on the 21.5 inch the same. For instance, would you need at least 2gb of video ram? Would the increase in gpu be enough to increase the overall price? Would intels integrated graphics at the end of the year or next year possibly be able to handle that kind of load without getting laggy?

Just curious, never been very savvy on GPU stuff.


macrumors 6502
Aug 10, 2011
The 13" rmbp runs 4k external screens at 52Hz without any dgpu.

Good point. Most integrated graphics nowadays have 4K ability. The big difference between these and high end graphics cards is the ability to play games on high settings at native 4K resolution.


macrumors 68020
Sep 27, 2013
I believe the only ting stopping current gen 21.5" iMac from using a 4K display is the Thunderbolt port on the back not being TB2. I think you can still use a 4K monitor, but it will only run at 30Hz rather than 60Hz.
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