Do you plan to use SLI or crossfire in the future? Does your motherboard support 2 video cards? What model and brand is your motherboard. If it supports SLI buy the nvidia, if it supports crossfire buy 6870 if you want to use 2 video cards.
I don't know the performance of the non TI version right now. Did not get the chance to search or read anything about it. Basically it's a stripped down version of the TI model, much like the GTX460 1Gb and 768mb. This version only has 336 cores, while the GTX560 Ti version has 384 cores.
I would invest a little more and buy the ti model since the difference in price is not that big. This is 230$ with mail in rebate http://www.newegg.com/Product/Product.aspx?Item=N82E168... .
500 Watt or greater power supply (Minimum recommended power supply with +12 Volt current rating of 30 Amps.)
at that resolution and with that cpu (not OCd)
i would go with the HD5850 or something similar
the $50 price difference wouldnt be worth it
for the performance gained (minimal difference in that setup)
I am pretty sure that the GTX 560 would be BNd by the CPU
unless you overclock
remember most games run on two cores
very few use the 4 cores
so you are basically using a dual core 2.93 to play games
your chip is respectable but to take full advantage of a card
like a GTX 560 you would need a good OC
even some of the I5/I7s are bottlenecks for the higher end cards
I would consider a GTX460 1gb to a good match for your CPU
get one of the good 460 OC editions like asus or HIS make
asus has the great Direct CU cooling and HIS has the IceQ series
if you OC the GTX 460 (ocing gpu is EASY)
then at your res you would be able to play any game
at good settins
also save yourself some bucks for future build (bulldozer?)