I recently came back into possession of my old G5 tower, and considering upgrading the RAM to use it as a workhorse for video editing. What's the most cost-effective choice, as far as compatible RAM sticks are concerned? Also, would the RAM be compatible with one of the newer Mac Pro towers, or would that be a separate investment?
You can use a variety of memory, inside the G5 tower, you are best off using the Crucial Memory Advisor as there are so many G5 tower variations.
It will most likely not be compatible with a new Mac Pro tower as they are now on DDR3, The latest G5 tower took Dual-Channel DDR2 PC4200.