The problem with older cards is support for codecs and hardware decoding. A GPU is depended on by other varying tasks outside of games as much as it is inside games now. For instance, a Geforce 6200 IGP on a really old AM2 board would work fine for Halo CE but try playing Youtube or have many tabs open and it'll be a laggy mess. Hardware decoding outside of games is a thing.
Take for example the HD630 IGP in my work laptop. It's backed by a decent Skylake i5 but I'm still having hiccups in Youtube, moving around tabs, scrolling excel sheets etc. Crappy video is half the reason why netbooks and the like never really took off back in the day.
The NVS 510 is worse off than a GT 240 and a GT 430. Take that for what you will in terms of relative performance.