I built my system two years ago with the Ripjaws F3-12800CL7D-4GBRM. Seems like today everyone is running 8GB or 16GBs. My MB supports up to 16GB (Gigabyte P55A-UD4). The 8GB kits are running about 50 bucks. Should I keep my setup the way it is or upgrade to 8GB or 16GB and try to sell the old one. I bought it for the low latency but seems like all the ones Im looking at are CL9s.
Depends on what you do with the computer and what you care about.
Personally I'm running less than 4GB(32bit system)and I haven't had a problem but I don't demand much from my PC and I don't run very demanding programs/games.
That being said if I had the cash I'd get 8GB at least.
RAM is kinda cheap and it doesn't hurt to have a decent amount.