In terms of overall gaming performance, the graphical capabilities of the Nvidia Quadro NVS 420 are massively better than the Nvidia GeForce 6150 SE 256MB.

The Quadro NVS 420 was released over a year more recently than the 6150 SE, and so the Quadro NVS 420 is likely to have better driver support, meaning it will be more optimized for running the latest games when compared to the 6150 SE.

Both GPUs exhibit very poor performance, so rather than upgrading from one to the other you should consider looking at more powerful GPUs. Neither of these will be able to run the latest games in any playable way.

The Quadro NVS 420 has 256 MB more video memory than the 6150 SE, so is likely to be slightly better at displaying game textures at higher resolutions. This is supported by the fact that the Quadro NVS 420 also has superior memory performance overall.

The Quadro NVS 420 has 11.2 GB/sec greater memory bandwidth than the 6150 SE, which means that the memory performance of the Quadro NVS 420 is slightly better than the 6150 SE.

The Quadro NVS 420 has 16 Shader Processing Units and the GeForce 6150 SE 256MB has 2. However, the actual shader performance of the Quadro NVS 420 is 9 and the actual shader performance of the 6150 SE is 1. The Quadro NVS 420 having 8 better shader performance and an altogether better performance when taking into account other relevant data means that the Quadro NVS 420 delivers a marginally smoother and more efficient experience when processing graphical data than the 6150 SE.

The Quadro NVS 420 requires 40 Watts to run but there is no entry for the GeForce 6150 SE 256MB. We would recommend a PSU with at least 350 Watts for the Quadro NVS 420.