If you don't care about DX11, then the card you have is quite good for a 17 inch monitor.
He doesn't have a card yet, or hasn't told us at least.
A 9800GT will be pretty good for 1280x1024 assuming that is the native resolution of your monitor. You mention Crysis however and that is one of the most intensive games around and the HD5770 would be more appropriate if you want to max out settings and use AA in that game.
Here is a general ranking of the cards you should be looking at with a low resolution monitor;
GTX 460 768mb > HD5770 > GTS 450 > HD5750 > GTS 250 > HD4850 > HD4770 > 9800GT > HD5670 > 9600GT > GT 240 > HD4670
The HD5670 and above will be good in general but if you are looking for something to attempt to max out the most intensive games like Crysis and Metro 2033 I would stick with the first few cards listed above.