1440p 75Hz
Radeon RX 5700
Up until recently only the Vega 56 made much sense in this price range (new) but those have been going up in price recently. The new 5700 (non-XT) at $349 is your best choice in this range. Consider spending an extra $50 for the XT variant as that will offer significant gains, but if your budget is strict, the 5700 will deliver. The 5700 also happens to fit into a small niche for gamers who own a 4K monitor and play mostly less demanding titles (think Isometric CRPGs, Grand Strategy Games, Indie platformers, etc) but like to play a AAA-game now and then at 4K. For $350 you get a GPU that will let you enjoy those less demanding titles at native 4K, while being able to give you an acceptable experience in triple-A titles at 4K using Radeon Image Sharpening+Scaling. Check the forums for a comparison between 4K native and 1440p upscaled with Image Sharpening.
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