4600HD Max pixel clock?

[Radius118]

Hi there!

Working on a problem with 4k60 resolution on a machine running i7-4765T with Intel 4600 IGP. A little background:

I have been trying to get full 3840x2160 @ 60 hz resolution out of the display port running at 594MHz pixel clock.

As it is, I can achieve this resolution using the Intel driver custom resolution tab but only using CVT-RB timing which results in a pixel clock of 533MHz.

The issue with that is I am using a device to split my HDMI signal. One signal is full 4K and goes to a 4K display. The other port downscales to 1080p. The problem is this device doesn't handle the non-standard timing of 533MHz properly. It simply passed this signal to the 1080p device which of course does not work.

So, I have been trying to figure out some timing numbers to get the pixel clock up to 594MHz. Nothing seems to work.

I am not sure if I am just not coming up with the right custom timing numbers, or if I am running into a hardware limitation, a BIOS limitation or a driver limitation.

Can anyone help? Thank you!