can you give some more details about what power supply, what gtx 970 you want etc...
also, the gtx 970 is a very good card for 1080 and 1440p gaming.
also has a very good price/performance ratio and doesnt require alot of power. doesnt get very warm etc.
and for the question, will the card fit?
see what card you want, look up the dimention of the card and then measure in your case if it will fit.