Dell has a number of its monitors on sale right now, but perhaps the best deal is on the 'S2716DGR' monitor (great name, I know). It's a 27" 1440p monitor, with 144Hz G-Sync compatibility. Right now, you can get it for $349.99 from Best Buy, a $250 drop from the MSRP.
The monitor also has built-in USB ports, a 1,000:1 contrast ratio, and a 1ms response time. For input, you get one HDMI connector and one DisplayPort. The only downside is that it uses a TN panel, but that's to be expected at this price.
You can buy the Dell S2716DGR from Best Buy here.
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