Flexboot ipxe.pxe Chainloading
If you have a large number of machines which already have a PXE implementation, then you may want to avoid having to reflash each machine's network card individually. You can achieve this by using chainloading.
To enable chainloading, you need to place a copy of iPXE on your TFTP server. Your machines will download this copy of iPXE from the TFTP server each time that they boot.
Before trying to chainloading ipxe.pxe, verify if the ipxe supports the hardware driver ID. For the NVIDIA device ID, see: https://ipxe.org/appnote/hardware_drivers