yes there seems to be a big difference with the grafix chip, and a 4-5 times faster card is only ~50 bucks more.
Mine is: ZOTAC GeForce GTX 560 OC 1024MB DDR5 PCI-E 256bit DVI-I DVI mini HDMI aktiv dual Slot
was 1 1/2 years ago ~150 euro, but not available anymore.
I think 650 chip is comparable nowadays:
http://www.alternate.de/html/product...arte/1028838/?
or
http://www.alternate.de/html/product...arte/1033779/?
would go with the 2gb version tbh. One thing that makes me wonders is the interface, mine has 256bit, but those have 128 bit ?