Ive got the HD 4550. 1GB card. Though it seems the highest my memory can go is 500mhz. When I open the Catalyst control centre, the highest I can set it to is 500mhz. So I'm wondering why its advertised as 1000mhz, but I can only actually get half of that.
More about4550 memory speed
It is Dual Data Rate effective 1000 Mhz actual 500Mhz!
Ok, so that means I am getting 1000mhz out of it? Sorry but I'm still learning about video cards.