4k 60Hz tip

[damian0815]

In case anyone else is struggling with getting 4k @60hz over DisplayPort, there's an important step that's often not clearly spelt out:

Make sure your SCREEN is set to DisplayPort 1.2 <- this is in the physical screen's configuration, not anywhere in OSX.

I wish someone had told me this before I wasted half a day on it.

(FWIW I have a GTX660 and an Asus PB287Q on DisplayPort, and an older Asus monitor on DVI. 10.9.3, have yet to try 10.9.5)

 

[damian0815]

Another tip: Put the card in a PCIe-x16 slot, not a PCIe-x4 slot like I did.

I guess it's stuff like this that makes people buy a real Mac...

 

[apple_hack_geek]

Really ? I doubt that 4x lanes would have trouble powering a card for just basic system operations. Do you have your display truly working at 4k @ 60 hz now ?

 

[cccip]

4k 60Hz is a Russian roulette these days. Be ready to be a beta tester.

If driving via external card - IGFX should be disabled, MST enabled, proper SMBIOS set, latest drivers loaded, not all displays well supported (even with DP1.2/MST enabled), my Dell 2414q going to sleep on OS boot and must be power cycled in order to show desktop.

Intel IGFX (4600) can provide 4K 60Hz only with no QE/CI acceleration

P.S. Now it boots properly without going to sleep and no need to power cycle each time. Solution - set BIOS OS Type to Windows8 and change CSM to Never

 

[slead]

4k 60Hz is a Russian roulette these days. Be ready to be a beta tester.

If driving via external card - IGFX should be disabled, MST enabled, proper SMBIOS set, latest drivers loaded, not all displays well supported (even with DP1.2/MST enabled), my Dell 2414q going to sleep on OS boot and must be power cycled in order to show desktop.

Intel IGFX (4600) can provide 4K 60Hz only with no QE/CI acceleration

I want to buy the same dell screen, the question is if a Radeon HD 7970 will be able to run 4k (UHD) without problems?
I got a i7 970 with 24 Gig of RAM and osx 10.10 running...

 

[cccip]

Yep, 7970 supports 4K@60Hz - it was able to do 50Hz in 10.9 and should be better in Mavericks (saw this some time back).
However I'm on nVidia and can only sign off for green cards...

 

[slead]

Yep, 7970 supports 4K@60Hz - it was able to do 50Hz in 10.9 and should be better in Mavericks (saw this some time back).
However I'm on nVidia and can only sign off for green cards...

you mean it should be better in yosemite, or am I mistaken?
Thanks for the info

 

[deutscs]

Thanks so much for the tip to stop monitor from going to sleep mid-boot - been really annoying me. Now just to get 60Hz working...

S

 

[the-darkvoid]

Try applying this patch to your Yosemite installation:

# Run the following command in order to patch IOKit in order to disable CheckTimingWithRange
sudo perl -i.bak -pe 's|\xB8\x01\x00\x00\x00\xF6\xC1\x01\x0F\x85|\x33\xC0\x90\x90\x90\x90\x90\x90\x90\xE9|sg' /System/Library/Frameworks/IOKit.framework/Versions/Current/IOKit
sudo codesign -f -s - /System/Library/Frameworks/IOKit.framework/Versions/Current/IOKit

This patch unlocks the maximum pixel clock limit in OS X, allowing you to drive a 4K monitor @ 60hz using the Intel HD4600 (and potentially other cards).


It will automatically create a backup as IOKit.bak in the same directory, should you want to revert the patch.


Give it a try and let me know the results.

 

[deutscs]

Thanks for that - i'll give it a try, but out of interest before I try it, is there any way to run this through Clover, rather than changing files in SLE?

S