Except for the newest Go 7 series, nvidia never made their drivers usable by default on mobile graphics chips. Even the Go 7 series specifically lists which model laptops they're supported on. It's unlikely they're going to make drivers that support the Go 6 series at this point, let alone making platform drivers for the 6150. They desire for you to get the drivers from the laptop maker, as the system may have been customized and they don't want to have to support it or be responsible if drivers designed for desktop systems don't work on your laptop. Of course the mainboard maker is just getting drivers from nvidia and customizing them.
There are some places you can get the regular nvidia drivers, but with their product ID information modified so that they'll install on mobile chipsets, but I can't think of where I found mine at the moment. That's what Google is for. But you're not going to get them directly from nvidia.