What brand of graphic cards is better ?

Are you looking at an Nvidia Card or ATI? It would swing my answer.

For Nvidia, my favorite brand is XFX hands down. Although Evga is good and several others. MSI is nice, whoever has the better cooler and better support.

ATI, Sapphire is the largest seller. Some people don't like them, however I have never had an issue. Asus is nice, I have an asus, their support is good and quick. HIS probably makes the BEST coolers, but you will pay for it, which sometimes isn't a bad thing because if you plan to upgrade your cooler you may as well go with one of their IceQ coolers.

Well here is jus a simple way to put it...
based on people's preferrence and not on the quality of the card...

EVGA,XFX > BFG, ASUS, MSI > PALIT, ZOTAC,rest...

I like cards that come with FREE GAMES!... That is always my selling point. Unfortunately this time they did not, although if I would have waiting 2 weeks I would have gotten STALKER Clear Sky, I was upset about that.

I think they all generally keep to the same reference design, so the cards themselves, all things being equal, should be similar in capability and reliability. What you want to go for are the warranties, extra goodies such as free games, upgrade programs, and the quality of their technical support. All things considered, I like EVGA.

I was thinking something like this:

For NVIDIA: EVGA/BFG/XFX

For ATI: Sapphire/XFX/HIS/ASUS

I always go for the cheapest price/warranty ratio. So far I have had cards from Pallit, MSI, EVGA, Sapphire, BFG and ATI, with one Sapphire card RMA after 18months of owner ship.