I have a Mac Pro from late 2007, early 2008 and I want to perform a clean install but nothing comes up on my monitor. The graphics card is an NVIDIA GT 120 and the hard drive is an Intel SSD. I am assuming the graphics card is the problem but all comments point to it being supported.
How do I do a clean Snow Leopard install with the given hardware?
The Apple NVIDIA GeForce GT 120 Graphics card is not compatible with the 2007/2008 Mac Pro, so in order to do the fresh install you will want to remove the GT 120 and re-install a compatible graphics card that will work with the 2007 / 2008 generation of Mac Pro.
As noted on Amazon the following system requirements are noted for the Apple NVIDIA GeForce GT 120 Graphics card.
Requires Mac Pro (Early 2009 with 1066MHz DDR3 memory) with PCI Express 2.0 slot
If you have reset the NVRAM to clear the device tree and let the mac have the best chance to run the installer, you still have some options to resolve this.
A newer retail OS X DVD should
have the original and updated
drivers to drive that monitor
(making a failure more likely
hardware and less of a driver
question) than the DVD that originally shipped with that model.
Taking the drive (or the whole Mac) to a shop that has all the boot images and several retail OS DVD on hand might be needed.
DeployStudio running on another mac has saved my day more times than I can count. Their boot loader is quite up to date - the closest to a universal image as I have seen. If that fails, you may have to resort to installing an OS to the drive connected to another mac in target mode or by a dongle for SATA drives.