Here are all the radiator sizes the Corsair Obsidian 1000D supports

[Windows Central]

Best answer: The Corsair Obsidian 1000D supports up to four 480 mm radiators simultaneously. The default configuration is two 480 mm radiators at the front and one 420 mm radiator at the top.
Best PC case money can buy: Corsair Obsidian 1000D $515 at Newegg
Best Radiator for the Obsidian 1000D: Corsair Hydro X Series XR7 $140 at Newegg

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