Conclusions
Jeez. We plow through all of those numbers, and I still can't declare any clear winner. What we do know is that, with the Radeon HD 4890 and its OC variant, AMD has succeeded in establishing a new standard for performance at the $249 price point. This is a most excellent development, and it has forced Nvidia's hand. Fortunately, Nvidia's response is quite respectable, as well. The GeForce GTX 275 is a worthy competitor to the 4890, and which card is a better value may depend on how prices shake out once both options are out in the wild. Remember, the 4890 OC card we tested costs $265, and if anything, it was an almost exact match for our stock-clocked GeForce GTX. Then again, the first GTX 275 has apparently popped up at Newegg as I write, and it's priced at $259.99. So perhaps the 4890 OC is the most apt comparison—and the parity remains intact.

That's not to say the cards are exactly interchangeable. Nvidia has biased its cooling solution in favor of higher GPU temperatures and lower noise levels under load, while AMD has done the opposite. Also, the 4890 OC draws less power under load than the GTX 275, but more when idling at the Windows desktop. You can choose which set of attributes you prefer there. The 4890 is physically shorter, too, which could be important inside of an especially cramped case.

If you think I'm gonna pick for you when things are this tight, though, forget it. This one is too close to call. My only advice is that you might want to consider carefully whether you need to pay for the extra performance in these cards versus the next rung down the ladder, like this Radeon HD 4870 1GB for $190 or this GeForce GTX 260 for $179. Those might be even better deals, and they may be all the GPU you need for current games, too.