nVidia drivers for Windows 10

Did you try installing this one?

http://www.geforce.com/drivers/results/56378

It's for Windows 7 / 8  but it might work for Windows 10.

we have a few workstations running nvidia geforce 210 cards (for dual display purposes) and there's a windows 10 driver available for it.

We can usually find them for around $30-$40.  We were buying 3 of them at a time and keeping them on hand.

This is the card we are running in about 7 workstations:
http://www.microcenter.com/product/380573/GeForce_210_1GB_DDR3_PCIe_20_x16_Video_Card

64-Bit windows 10 driver: http://www.nvidia.com/download/driverResults.aspx/87988/en-us
32-bit windows 10 driver: http://www.nvidia.com/download/driverResults.aspx/87986/en-us

I'm sorry but your suggested solution is very unclear.  Simply pointing us to another website that is also unclear is not a good solution.  Is there a workaround or not?  If so, can some please be more articulate about the process to make a Windows 7 system with the Nvidia-GeForce6150SE nForce430 installed card get Windows 10 and make it work with this card.  Right now, W10 is telling us that it will not download the software because it is incompatible and the detail points to the Nvidia card.

From the link above
"Download the Windows 10 ISO file manually from Microsoft, run the setup but skip the update/online check. Install the 309.08 driver after installation."
You don't need to wait on the upgrade installer to install Win 10 from their direct download

Did you try the driver I suggested?  

http://www.geforce.com/drivers/results/56378

It's for Windows 7/8, but it might work with Windows 10.

I'm not sure that helps him if he has already upgraded the computer to 10

Haven't had a chance to try this solution but other searches indicate that this should work.  Will try it in the next day or so.