I'm not familiar at all with overclocking so I have a couple questions to be answered before I chose a graphics card for a new system. I'm looking to purchase an 8800 GTS 640mb at either 576mhz OC'd or core 500mhz.
1. Do manufacturer overclocked graphics cards run hotter than a normal core speed graphics card?
2. Do manufactuer overclocked cards tend to have a shorter life than a core speed card?
There doesn't seem to be much of a difference in price for the 76mhz increase, so I'm just concerned about the life of the card and overheating problems (even though I'll be getting an Antec 900 case). Any help would be greatly appreciated.
1. Yes they will (unless there is a custom cooler installed, not usually the case)
2. Generally yes they will have a shorter life, however, this is negated by the fact that most GPU manufacturers warrant there cards for 3 years and some warranty for life of product. So even if there is an issue with failure it can be repaired under warranty.
If you dont have OCing experience and dont intend to give it a try (with obvious risks) then a factory OC'ed card will be the best option especially if stock cards are similarily priced.
As you suggested a good air flow case will partially negate the potential heat increase of the OC'ed cards, of which the Antec 900 is a good choice.