So i'm building a gaming pc. I'm going to be playing World of Warcraft and COD4 mainly. I'm not a Vista fan and will be using XP PRO 64-bit most likely. If everything else in the machine was the same except the video cards would 2 8800 Ultra or a 9800 GX2 give me better performance and fps while gaming? Would appreciate someone more knowledgable with video cards and building pc's to help me out. Also considering getting 1-2 280 GTX's but the cost and power consumption has me leaning away from them.
A single 4870 will do just fine for WoW and COD4, and anything else that's out right now (assuming you don't play on a 30" monitor). If you're building this PC from scratch then I'd seriously consider getting a Crossfire board instead and going the 4800 route. They're just a better value right now, and depending on how well it scales a 4870+4870X2 system would blow anything but 2xGTX280's out of the water.