Questions on video card/graphic card?

Recently i am looking at dell desktop and wanted to buy one but i am not sure whether i should get a 128mb video card or a 256mb video card. I am not a hardcore gamer but more like a hardcore music fanatic and occasionally, will watch movies both online and from dvd. Is it necessary for me to get a 256mb one instead of a 128mb? Oh ya, its on window vista. Thanks ppl.|||128 will do for you|||id get a 256 card cuz i had a 128 on my old comp and it just wasnt cutting it. go for a gforce 7900, theyre pretty good still and cheap in price.|||128 will be more than enough for you