KC after posting I checked the specs of the ATI XFX HD4350.As I suspected there was a confusion in how you read it.It offers 8 Gbs of band memory not of graphic memory.Thatīs what it says on the website.
There are 2 types of HD4350, one with 512 mbs( the cheapest at $ 40 probably) of video memory and the other with 1024 more expensive).
For $ 30 more you get double the video memory so if you can afford it go for the model at $ 70 this way you wonīt have to upgrade in 6 or 7 months and prices may go up.
All in all both are pretty decent cards.