I'm using the two DisplayPort ports on this dock to connect two 4K monitors (Seiki SE39UY04 39" 4K Ultra HD 120Hz LED TV (discontinued)) from modest Intel 4400 EliteBook 850G1 15 graphics chipset 0.6 " LED to connect Intel Core i7 2.1GHz 16GB SDRAM 256GB SATA SED Windows 7 Professional 64-bit. Each monitor's HDMI cable connects to the dock via an active male DisplayPort to HDMI adapter (supports displays up to 4K/UHD/3840 x 2160 @30Hz). By default monitors have a refresh rate of 29Hz. They are rated at 30Hz and if I want I can select 30Hz from the Windows 7 Enterprise drop down list. But I have no reason to tempt fate. My employer provided a dock at work, but I liked it so much that I bought it to use at home on snowy days.
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