Vray rt cuda GPU help

[Dribbler]

Hi everyone.. I'm running an older PC consisting of the following

Gigabyte GA-P55A-UD3R (rev 1.0) Motherboard
i5 750 @ 2.67GHz Processor never overclocked
12gb ram 1600Hz Running at 1333Hz
Current GPU Gigabyte nvidia GeForce GT240
550w PSU
Windows 10 64bit

I have been modelling on sketchup 2016 64bit with vray 2.0 rendering with the CPU... For a quite detailed scene it takes about 1.5 hours to render and I'm more than happy with the results, however I would like to speed up the render times and am looking at purchasing a msi GeForce GTX 970 4gb

So my questions are will vray rt cuda work with this GPU?
Am I going to notice a big speed difference?
Will my final renders be better quality or not as good as what I'm getting from the CPU?
are there any known issues with rt and or any issues with using this card?

Also will this be ok with my system?

Thanks all.

Sorry if this is posted in the wrong area.