You may mistake cards like the Mobility Radeon HD 545v for the Mobility Radeon HD 5450, but this is not the case as these new GPUs with a "v" suffix are rebrands of the Mobility Radeon HD 4000 series, they are made on a 55nm process and lack DirectX 11 support.
Rebrands:
Mobility Radeon HD 560v series = Mobility Radeon HD 4600 series
Mobility Radeon HD 540v series = Mobility Radeon HD 4500 series
Mobility Radeon HD 530v series = Mobility Radeon HD 4300 series