T430S - need help outputting 4k resolution

[tmhardie]

I don't know where you're getting your information. The T430s cannot drive 4k on DisplayPort according to Lenovo:

http://support.lenovo.com/en_US/detail.page?DocID=PD024706

• Maximum external resolution: 2560x1600 (DisplayPort)@60Hz; 2048x1536 (VGA)@75Hz; 1920x1200@60Hz (single-link DVI-D via cable 45J7915)

I specifically upgraded to a T440s to get my Seiki 4k screen working. It works fine with an active display port to HDMI 1.4a adapter directly connected to the laptop. It does NOT work through the dock (The dock is not properly compliant for the higher clock rates in DisplayPort 1.1, despite claiming it is)

[lead_org Microsoft MVP Contributor]

Lenovo spec for the t430s was written up when 4k resolution does not exist yet.

[ibmthink]

It did already exist, maybe not yet on the mass-market, but all the plans were already there. 

As tmhardie posted: The T430s does support 2560x1600 as maximum over DP. The only Ivy-Bridge machine with 4K support is the W530 (which also proves that 4k already existed), since the W530 has DP 1.2

All new Haswell machines support 4K, but some only @30Hz (like the T440s with HD4400), and some with 60Hz.

[lead_org Microsoft MVP Contributor]

http://m.youtube.com/watch?v=wdU2c6clEds

The hardware itself can Support 4k. But the new 4k monitors require either hdmi 1.4 or dp 1.2 with MST, which ivy bridge cpu don't support.

Just like the ivy bridge CPU can 32 gigs ram across two ram slots, but Intel deciding that it didn't want to release bios firmware to enable that feature.

Correction: The T430s can support 4K@60 hz when two displayports are used. If using only one displayport, 4K resolution can be achieved only when you have a refresh rate of lower than 30 hz. 

[dantheperson]

I can confirm 4K works with a T430s.

I used the 'custom resolution' (right click on desktop) of the intel windows driver to define 3840x2160x25Hz.

This is connected with display port to a Samsung U28590D with mini DP to DP adapter.


I'm not doing video or gaming so 25Hz is OK.