Graphics cards: when is an upgrade not an upgrade?

I don't even want to think about how many graphics cards I have "upgraded" to in attempts to run various incarnations of TS better.
For several years, I've been using an EVGA GeForce 2GB GTX 550Ti with reasonably good results, but there's always the temptation to move on up, isn't there? So when I saw a sale at Amazon for a GeForce GT 740 4 GB (single slot model), I figured that the higher number plus an additional 2 GB memory had to be better. The card arrived, I installed it, and I really cannot see an improvement in terms of fps or graphics in general. The old GTX 550 Ti required a power connection, but the new GT 740 does not. Since I can return the GT 740 easily (blessings on Amazon), I just ordered a double-slot version of the same card that does require a power connector.
Thoughts? Am I going around in circles? perhaps even backward? Will Santa bring me better knowledge about any of this for Christmas?

For several years, I've been using an EVGA GeForce 2GB GTX 550Ti with reasonably good results, but there's always the temptation to move on up, isn't there? So when I saw a sale at Amazon for a GeForce GT 740 4 GB (single slot model), I figured that the higher number plus an additional 2 GB memory had to be better. The card arrived, I installed it, and I really cannot see an improvement in terms of fps or graphics in general. The old GTX 550 Ti required a power connection, but the new GT 740 does not. Since I can return the GT 740 easily (blessings on Amazon), I just ordered a double-slot version of the same card that does require a power connector.
Thoughts? Am I going around in circles? perhaps even backward? Will Santa bring me better knowledge about any of this for Christmas?

