since there seem to be great price differences on the cards with that chipset, I wanted to ask for your oppinions. I am set on going for an ATI 7970 card, the vanilla version not OCed. I understand the OCed versions cost a bit more. However, there seem to be different no OC versions within the same manufacturer and I cant figure out the difference.
Example (taken from alphacity.co.nz):
Sapphire HD7970 3G PCI-E 3.0 GDDR5 PCI-E Video Card , 925MHz / 1375MHz , 384bit , HDMI+DVI-I+DUAL MINI Display Port, The Latest AMD Gaming Card - 650 NZ$
Sapphire Radeon HD7970 3GB GDDR5 PCI-E HDMI / DVI / Dual Mini DP - 610 NZ$
The major difference between the MSI brands, is the reference (original) card versus the lightning (non-reference) meaning that it has a custom cooler. I am also thinking it would be the same for the sapphire's. You can't go wrong with MSI though, I like their quality.
The MSI Lightning is the best one that list and its one of the most popular on the forums here. It's got a very well deserved reputation because its factory clock settings are very nice and the cooler is very good. Out of the box it will beat the GTX 680 quite handily due to the factory settings (1070 OC on the core vs 925 reference, a nice 16% overclock). The chips used are also of higher quality, most lightnings will easily hit 1100, or even 1150 with some hitting 1200 or above. It's definitely worth the extra money.
I personally have two Gigabyte 7970s with the Windforce 3 coolers:
Most of the 7970's overclock very well. You will be able to achieve high core clock even with a reference board. The quiet and more effective cooling is really what you're paying for. As well as reducing the chances of getting a board that doesn't OC well since they are factory tested prior to your purchase.