legacy PXE vs UEFI pxe

[maya]

I'd like to know where I can find documentation on how legacy vs UEFI PXE is loaded into BIOS..and the differences in the two methods with respect to the BIOS.

I'm hitting an error with legacy PXE (because I think my NIC isn't programmed properly). However, iPXE off usb works fine.

Any documentation which explains this clearly would be helpful.
Thanks

[robinsmidsrod]

If you're having an issue with legacy PXE (chainloading as we like to call it) you should carefully review the chainloading howto and se if either undionly.kpxe or ipxe.pxe works on your hardware.

iPXE using UEFI is a completely different ballgame and is not yet considered stable, so you should avoid it unless you're feeling adventurous. You can find a bit of info about iPXE's EFI support here: http://ipxe.org/efi/vision