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We study the current and temperature dependences of the microwave voltage emission of spin-valve nanopillars subjected to an in-plane magnetic field and a perpendicular-to-plane current. Despite the complex multilayer geometry, clear microwave emission is observed for current densities in the interval 9×10 7 to 13×10 7 A cm −2 . The emission frequency stays near 12 GHz when I < I red = 11.2 × 10 7 A cm −2 , then redshifts with a slope gradually reaching -350 MHz/mA for 16 × 10 7 A cm −2 . The linewidth narrows exponentially to 3.8 MHz at 150K for I < I red , then broadens again as the emitted voltage redshifts. The temperature dependence of the linewidth exhibits a curvature change around the linewidth minimum.