Wales had the game wrapped up early on and though Argentina had a burst of scoring in the last minutes of the match the result was never in doubt.
Cardiff fly half Nick Robinson had another splendid day with a 25-point haul from a try, four conversions and four penalty goals.
The five tries scored took the Wales try-count to 17 in two matches with scrum half Michael Phillips (Llanelli), wing Lee Roberts (Cardiff), full back Gareth Swales (Swansea) and flanker Robin Sowden-Taylor (Cardiff) all joining Robinson in touching down for Wales.
Team:G Swales; L Roberts, M Jones, M Brayley (capt) (M Miles), M Nuthall (M Hook); N Robinson, M Phillips (C Miller); P James, A Matthews, A Jones,
Rhys Jones, L Tait, R Williams, R Sowden-Taylor, Ryan Jones (G Williams).
Tries: M Phillips, N Robinson, L Roberts, R Sowden-Taylor, G Swales. Cons: N Robinson (4). Pens: N Robinson (4).