Nice choice for MorphOS hardware.

I use a Single processor dualcore system, updated to the 2.5GHz cpu. Daily driven for 3 years and bullet proof, and overkill for most needs... :)

A few words of advice and comments to help:

1. You can put an NVIDIA PPC card in the lowest slot and the 1950 in the third slot. This will provide OF support and boot just fine into MorphOS.
2. Please note it will boot with just the 1950 right to MorphOS, you will have to set the PM to boot first from the CD.
3. I have seen certain configurations not boot consistently to MorphOS, requiring rebooting to get it hooked up, with just a PC based 1950 card. You might be able to flash it and be good to go.
4. It might also work best with using a sandisk ssd or hdd to boot from, you can use a real fast ssd as a secondary drive that houses all the data.
5. I realize you bought a card already, but there is a list somewhere for what cards work and what ones don't.
6. With your use case, likely not an issue, but if you drive 2 monitors with lots of stuff going on for serious productivity. A 256MB VMEM video card will be best, as it never will swap out if you run out of vmem (creating a slow moment for the swap).

The 1950 is the best option for 3d currently, 2d is just fine as well.

Good luck.