By comparing the benchmarks of the two cards, the HD6870 is superior in those games that I want to play. What I want to know which of the cards perform better on the Source engine (Looking @ TF2), that probably will decide which card I take. And would it really pay back getting a MSI GeForce GTX560 Ti, 1GB, GDDR5, Twin Frozr II in the long run ? And if I buy a 600W psu and use it with this build will it be less power efficient then a 500W psu?

[...] such as buying nvidia because you are a fanboy. i honestly cant believe people can use these shit excuses, when the underlying issue is not the hardware behind the brand, it is the brand itself and that you are an easily convinced consumer who will by the product that gets advertised the most. this is like saying there is more to a book than just reading it; you can use it to wipe your arse as well. consider what a graphics card does in a gaming system..... renders 3d. edit: also i once owned an nvidia fx5200 which had bad drivers and would not run css well. therefore all nvidia card future generations are shit (this is your own logic) past experience with a brand of graphics cards when there are only 2 companies competing in the gaming market is a very flawed way to judge due to the extremely high level of competition to control the market and therefore huge amounts of cash going into the development of new hardware, drivers, better support, and advertising. This will cause the "best card of the moment" to be a very volatile thing indeed.

[...] No, I also base it on my own experience. Besides, there is more to a gpu than just 3d rendering.

I'm not a fanboy or anything, I considered buying an ATI card cuz it has better performance than equivalent nvidia cards, I just have herd more people complain about their ATI cards, than nvidia. So what you wrote is not what I think at all.