Radeon 7670M is better than the NVIDIA GeForce 630M. They aren't even comparable. If you want a fair comparison you should look at the 650-660M.
AMD Radeon graphics cards are ranked in performance by the hundreds with the tens place being for designation of more specific features, and the thousands for the generations, generally. With NVIDIA, the hundreds marks the generation and the tens marks its rank of performance.
For example, a Radeon 7990 is the latest and highest performing gpu from AMD right now, and the 690 is the latest and highest performing gpu from NVIDIA.
Edit: with Lex's input above, it'd really be best if you found a comp with that 7670 card, the i7-3630QM, and a 7200 rpm HDD. Also, found a sentence: "The $555 i7-3630K, which fundamentally the same the $990 i7-3960X, just clocked 100MHz lower and with a little less L3 cache, is definitely the processor to choose if you're going to be building a high-end system based on the LGA2011 platform."
I'd rather go for the i7 and forgo the graphics but keep the 7200 HD, since the cpu can pick up the slack for graphics.
EDIT 2: NVIDIA has 8800s and so on as well. The GTX series tend to have 3-digit numbers. Same deal applies four the 4-digit numbers as that with Radeon cards, but without the tens place.
Edited by Waker, 26 November 2012 - 02:51 AM.
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“I divide my officers into four classes; the clever, the lazy, the industrious, and the stupid. Each officer possesses at least two of these qualities. Those who are clever and industrious are fitted for the highest staff appointments. Use can be made of those who are stupid and lazy. The man who is clever and lazy however is for the very highest command; he has the temperament and nerves to deal with all situations. But whoever is stupid and industrious is a menace and must be removed immediately!”
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