Sleek but pricey. Testing the latest CPU coolers on our new AMD Ryzen 9 3950X test platform has proven instructive. Noctua's NH-D15 chromax.black, be quiet!'s Pure Rock 2 and Corsair's iCue H115i RGB Pro XT have all been put through the wringer, with varying degrees of success, and today we're turning our attention to Fractal Design's Celsius+ S28 Prisma.