Upgrading graphics card, advice please :)

ok so simple, im updating my graphics card, at the moment i have a ATI radeon HD 5670 1gb

up until now the cards been great, plays most games on high, struggles a little on ultra on some games, but the thing thats annoying me is i upgraded my ram to 4gb only to notice the card uses 1gb of PC ram, stupidly i didnt check when i bought it, but the upside is now i know so any ideas on what to upgrade to?

i would like to spend under ВЈ90 / $140 although i can usually get them cheaper on ebay anyway with a little patience so you can go slightly over

it was suggested that i get Nvidia GeForce GTX 460, anyone got one give me an idea of there rig and what gaming is like for them?

just one thing though, please dont post if you have no idea what your talking about, dont mean to sound like a dick its just i did this a while ago for upgrading memory and all i got was a 100 people telling me theres is awesome and that i should buy that, a little knowledge or comparison work is always more helpful

cheers