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Really only 30hz at that price point? Seems like it should be 60hz - hopefully a missprint.
Thank you for your inquiry. Its native DVI-I resolution supports up to 2560×1600 @60Hz. When connecting at UHD resolutions, the SDN-4s supports up to 3840×2160 @30Hz. This is a typical refresh rate for other 4K NIAP Certified Secure KVM switches in this class and price range.

The extra expense of this class of KVM is mainly found in the additional security features and certifications required in certain high-security environments and applications.
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