sapphire tends to focus more on home theater then other video card manufactures
the 4850 tends to be a bit louder then the 4670 and demands more power but if you have a decent 500w PSU then its not an issue. In return its a far better gaming card, considered a mid-level card.
the 4670 can run any current game out there on low-med settings and can easily max out older games (pre-2005), Sims games, and a few others. Its an OK entry gaming card.
the 4830 would be in-between the 4670 and 4850 in terms of gaming performance. It needs less power then the 4850, offers HDCP, but costs as much as the 4850.
If you're not going to game then all you really need is a Radeon 4350 or 4550. This one from MSI has an HDMI connector on the board eliminating the need for an adapter.
Well I would like the option to run some games. I havent really tried any yet, the PC I used to have was a bone stock HP.
Let me ask another question. I notice that graphics cards tend to have the same numbers. For example The one above was a "Sapphire 4670"
But then a few posts down someone recommended a "HIS 4670"
Is the model number a standard across brands? If so how do you know what brand to go with?
ATI and Nvidia focus on creating graphic chips and card architecture, granted ATI has made some cards. Manufacturers (XFX, evga, ASUS, Sapphire, HIS, etc.,) then take these chips and architecture to create video cards. So when you see a 4670 from from two companies like HIS and Sapphire, the card uses the exact same chip, architecture, and usually (not always) uses the same RAM. The differences are usually on the cooling, HT features like a HDMI port, and sometimes over-clocked speeds.