My edit machine is a 2009 8 core, 2.26. GFX cards are both NVidias, a GT120 and a GTX285, as the machine was built for Resolve last fall. 6GB RAM.
I switched the monitor outputs from the GT120 (as this is what Resolve needs, and has been that way from the beginning), to the GTX.
Talk about everything in real time, without a single problem or hiccup. The GT120 wasn't bad, but the GTX is another story altogether. The most complicated Motion/Title templates are lickety split on the timeline, scrubbing with ease in real time without rendering.
Just an FYI for you all...
I wish I could leave it with the GT120 driving the monitors AND get FCPX to use the GTX for heavy lifting. Oh well.