iMac 5k

[AlDavis]

What's the benefit of a 5k iMac if the video card inside of it is only 4k? Who makes a 5k video card?

 

[casperes1996]

... What? The GPUs can output 5K just fine. They can also output6K and compressed 8K

 

[AlDavis]

... What? The GPUs can output 5K just fine. They can also output6K and compressed 8K

Please excuse my ignorance and explain. According to AMD, their video cards resolutions is up to 4k. How can a 4k video card produce a true 5k resolution? Not software compression, but from the output of the card. Please explain.

 

[calderone]

Please excuse my ignorance and explain. According to AMD, their video cards resolutions is up to 4k. How can a 4k video card produce a true 5k resolution? Not software compression, but from the output of the card. Please explain.

Where exactly are you seeing 4k?

What are you saying simply isn't true, the maximum digital resolution for the 570X is 7680 x 4320.

 

[AlDavis]

Where exactly are you seeing 4k?

What are you saying simply isn't true, the maximum digital resolution for the 570X is 7680 x 4320.

AMD Radeon™ RX 570X

AMD Radeon™ RX 570X graphic card with 32 compute units, 256 bit memory bandwidth provides advanced HD gaming experience. Learn more about its specifications!

www.amd.com

4k 60hz on website and I'm just repeating what is being said. I'm confuse now.

Analyzing the iMac 5K Retina display: How do you get 5K @ 60Hz from a last-gen GPU? (updated) - ExtremeTech

Apple's new 5K iMac is something of a puzzle - as is the resolution the display runs at. How's Apple pulling this one off?

www.extremetech.com

 

[calderone]

AMD Radeon™ RX 570X

AMD Radeon™ RX 570X graphic card with 32 compute units, 256 bit memory bandwidth provides advanced HD gaming experience. Learn more about its specifications!

www.amd.com

4k 60hz on website and I'm just repeating what is being said. I'm confuse now.

Analyzing the iMac 5K Retina display: How do you get 5K @ 60Hz from a last-gen GPU? (updated) - ExtremeTech

Apple's new 5K iMac is something of a puzzle - as is the resolution the display runs at. How's Apple pulling this one off?

www.extremetech.com

The 4K60 clearly show that is over HDMI which has limitations (limitations that don't matter for the iMac).

The extremetech article you link gives you the answer:

but in either case, there’s clearly enough bandwidth to drive a 5K display at 60Hz.

Apple is using custom timing controller to drive the display from these GPUs.

The full text:

Updated November 4: An iFixit teardown shows that Apple did indeed use a customized TCON — a modified Parade Technologies part using a non-standard 60-pin Embedded DisplayPort (eDP) connector (it’s usually just 40 pins). We’re not sure if Apple is using a variant of eDP 1.3, or some own Frankensteinian solution that combines two eDP 1.2 feeds — but in either case, there’s clearly enough bandwidth to drive a 5K display at 60Hz.

Keep in mind, this article is old and refers to older GPUs back when the 5k iMac was launched. The current GPUs do not have the same limitations and are able to drive 5k over DisplayPort 1.4 which supports 5k @ 60 natively.

 

[AlDavis]

The 4K60 clearly show that is over HDMI which has limitations (limitations that don't matter for the iMac).

The extremetech article you link gives you the answer:


Apple is using custom timing controller to drive the display from these GPUs.

The full text:


Keep in mind, this article is old and refers to older GPUs back when the 5k iMac was launched. The current GPUs do not have the same limitations and are able to drive 5k over DisplayPort 1.4 which supports 5k @ 60 natively.

Got it!!👍