Secondipity via Newegg offers the refurbished Acer Predator 27" G-Sync IPS WQHD LED-Backlit LCD Monitor, model no. XB270HU, for $599.99 with free shipping. That's $20 under the lowest total price we could find for a refurb sold elsewhere. (It's also $128 below the best price for a new one.) This gaming monitor features a native resolution of 2560x1440, Nvidia G-Sync technology, 144Hz refresh rate, and 1,000:1 contrast ratio. Deal ends August 8.
A 90-day warranty applies, although it's unclear who provides it.