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5570 compare to 8400? No you won't. They are both not full fudge gaming cards. If you are intented on gaming (as in FPS games, not Sim City or RTS games etc), you have to get 4770 or 9600GT/9600GSO/8800GT/9800GT as bare minimum to get reasonable amount of frame rate for FPS gamings...Will that offer a noticable increase of what I have already got?
5570 compare to 8400? No you won't.
They are both not full fudge gaming cards. If you are intented on gaming (as in FPS games, not Sim City or RTS games etc), you have to get 4770 or 9600GT/9600GSO/8800GT/9800GT as bare minimum to get reasonable amount of frame rate for FPS gamings...
If you try to cut corner on the card you are getting, you'd only be disappointed when you can doing some gaming...
Like I said, if budget is a problem, consider 2nd hand gaming cards instead.