The one that I use is Passmark Performance Test.
http://www.passmark.com
I notice that they are up to version 5.0 now, I am still using version 3.5
It is not free but you can download a trial version that will include seven computer configurations to compare to. You can try it and see if it does what you want.
..
So I have a brand new computer. I would like to know how it perfroms. Are there any programs which I can download to 'scan' and/or 'test' my computer and then generate a performance report so that I can compare my machine with other machines, with reference to a known standard ? Thanks,
christy.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic