I'm a forty year old father of two in a centrally-heated four bedroom home. My power bill is calculated by the KW/h. My PC graphics card is insignificant in the overall cost.
If you say so.
So what's your point?
If you're saving 50watts an hour that's potentially 1.2 KW/h a day, or $3-4 a month for someone that leaves their PC on all the time (or for someone like me who powers down when its not in use its about 1/3 of that). You don't have to be a tree hugger to just use good sense, but the fact that it helps the environment isn't exactly a downside.