what format are you editingin, and format of export. 41 hours is very long.
more memory has a performance gain on mainly mepg exports.
Have a look at my score with the 5.01 update I went from 95 sec to 34 secs with mpeg-2 dvd. with the current 5.02 time has went to 24 secs.
it may help you if you do the benchmark, as this will show the bottelneck of your PC.
Yes with the initial testing I did Friday with the 5.0.2 and our internal benchmarks, the results were considerably better with a 970 at stock over the 980 we did in the initial internal benchmarks. Adobe has made some nice performance optimization. Programs will normally only use the amount of ram that is available accept at certain points like when it goes to write a file on a drive. That is why its hard to tell when more ram will benefit the programs your using. In the case of CS5, 12 GB is rarely minimum of where you want to be and 24GB will handle most editing workflows with some to spare. So yes increasing the ram to 24 GB will help.