She was initially assigned to the China Station and then provided landing parties which fought in the Siege of Ladysmith of 1899–1900 during the Second Boer War.

[1] The engines were designed to produce a total of 25,000 indicated horsepower (19,000 kW) at forced draught[2] and gave a maximum speed of 22 knots (41 km/h; 25 mph).

She carried enough coal to give her a range of 7,000 nautical miles (13,000 km; 8,100 mi) at 14 knots (26 km/h; 16 mph) and her complement consisted of 894 officers and ratings.

[3] Powerful was laid down by Vickers Limited in their Barrow-in-Furness shipyard on 10 March 1894[4] and launched on 24 July 1895 by the Louisa Cavendish, Duchess of Devonshire.

During a full-power run between Wei Hai Wai, China, and Yokohama, Japan, in late July 1898, her stokers mutinied, but she then visited Port Arthur without incident.

The ship departed Hong Kong, China, on 17 September and arrived at Simonstown on 13 October, two days after the Second Boer War began; Lambton having picked up a half-battalion of the King's Own Yorkshire Light Infantry from the island of Mauritius on his own initiative.

After a request from Lieutenant General George White, commander of the besieged forces at Ladysmith for more long-range artillery, Powerful ferried all four guns to Durban, reaching it on 29 November.

Queen Victoria sent a telegram saying, "Pray express to the Naval Brigade my deep appreciation of the valuable services they have rendered with their guns.

... A more eager, joyous gathering I never saw.....We cheered, we waved hats and handkerchiefs and we were half wild with delight.The naval brigade paraded for Queen Victoria at Windsor Castle on 2 May.

[22] A Sydney Morning Herald journalist, Charles Bean, joined the ship in August 1908 as a special correspondent to report the visit of sixteen American warships – the Great White Fleet.

[24] The ship was ordered home in January 1912 and loaded the body of Alexander Duff, 1st Duke of Fife at Port Said, Egypt, on 9 March en route.

After arriving, she was briefly assigned to the 7th Cruiser Squadron of the Third (Reserve) Fleet[25] before she was reclassified as a boys training ship at Devonport in August 1912.