With a price cap of $300, the ASUS Radeon Extreme AX850 XT is your best buy. It connects through a PCI-Ex16 connection, has 256MB of GDDR3 VRAM on a 256-bit interface, has 16 pixel pipelines, has dual DVI outputs, supports VIVO for video input and output (for your video editing), comes with an impressive bundle of software and cables, is very highly rated (not just on Newegg but also on many benchmarking and gaming sites), and has very good thermal properties. This is a two-slot card, meaning that it will occupy the slot that it resides in and will cover over the slot below it because of the design of the cooler. The cooler is very large and is very loud at system startup, but after post, the cooler is actually very quite.
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