To compare the ranks of the CPUs.
There are clock rates and multiple cores.
How to compare the ranks of graphic cards?
ATI and Nvidia?
This ranks graphics cards (doesn’t include the new nvidia Fermi cards):
http://www.tomshardware.com/reviews/best-graphics-card,2569-6.html
And you can compare specs with these:
http://www.gpureview.com/show_cards.php?card1=580&card2=579
http://www.upgraderguides.com/hwdb.php?type=1&page=details&dev=182&dev2=37
Google benchmarks
References :
You look at benchmarks. They will generally name their products accordingly. Like GTX 260 is less powerful than GTX 285.
As for CPUs, the best out are the i7. The lower priced but similar in power i5s are also decent. Those are quads.
References :
This ranks graphics cards (doesn’t include the new nvidia Fermi cards):
http://www.tomshardware.com/reviews/best-graphics-card,2569-6.html
And you can compare specs with these:
http://www.gpureview.com/show_cards.php?card1=580&card2=579
http://www.upgraderguides.com/hwdb.php?type=1&page=details&dev=182&dev2=37
References :