Commissioned in October 1780 under Captain Charles Wolseley, "Magnanime" sailed in 1781 with the Relief Expedition to Gibraltar, and subsequently to the Indian Ocean, where she participated in several of the series of battles against French forces off India – including those of Providien, Negapatam and Trincomalee in 1782 and Cuddalore in 1783. She returned to the United Kingdom and paid off into ordinary in June 1784.