2016 15" MacBook Pro with 4K external display

[kart]

hi guys.
I currently own a mid 2014 15" MacBook Pro 256gb and have just purchased a LG 4K monitor which I now use with the MBP. It runs at 60hz from the MacBook Pro, however there is slight lag on the 4K monitor when using Photoshop, Lightroom etc. I am wondering if the new 2016 512gb MBP with touch bar 15" will have the same problem. The 15" 512gb 2016 model has a 2gb graphics card (bigger and better then my 2014 model), and I am wondering if this will eliminate the lag on the 4K monitor, especially since the 2016 MBP can drive a 5k external display.
Will I still get 60hz with a USB C to DP cable?

Much appreciated

 

[Mindinversion]

I can't say about USB C to DP cable, but I CAN tell you I have an LG 27UD88. . . and my 2016 MbP w/ Radeon Pro 460 drives it smoothly @ 60Hz. I wouldn't attempt 4k GAMING on one, but should eliminate any lag with photo editing.

 

[kart]

I can't say about USB C to DP cable, but I CAN tell you I have an LG 27UD88. . . and my 2016 MbP w/ Radeon Pro 460 drives it smoothly @ 60Hz. I wouldn't attempt 4k GAMING on one, but should eliminate any lag with photo editing.

Ok, I have the LG 27UD68 as I purchased it for use with my 15" mid-2014 MBP (had no need for the USB C at the time)
Very similar displays and I am looking at using this display with the 2016 MBP (if I upgrade.)
Do you use CC Photoshop, Lightroom or Premier Pro? If so, do you find lag when using any of those application when on the 4k monitor? This is the problem that I am currently having, my Mid 2014 MBP lags when using CC Photoshop, Lightroom or Premier Pro on the 4k monitor. I am assuming that the graphics card is not up to scratch in powering the 4k monitor @ 60hz. I do not have this issue at all when using these applications on MBP.

Much appreciated.