Found the issue with the setup:
1.) 4-pin ATX +12V connection was NOT plugged in. (fixed that)
2.) The Rosewill PSU has only a single 6-pin PCI-e connector
The video card requires 2x 6-pin PCI-e cables. The 8-pin I spoke of is an EPS +12V connector.
So, looks like I need to purchase another PSU anyway with 2x 6-pin PCI-e cables.
Corsair PSU
Thank all of you who helped with this first build speedbumps, expecially my friend who pointed out the missing CPU power cable.