Is it worth it?

[morkfromork]

Hello guys i have a single ati radeon hd4850 512 in my computer at the monmet. I play lots of diffrent games dod:s gta4, world at war and crysis and other fps games.

I'm looking at crossfire with another 4850 512 but will i really notice a diffrence or am i better off sticking with what i have or maybe selling it and getting a better card?

Cheers in advance

 

[morkfromork]

Would i notice much of a diffrence by upgrading it or will it be just a little jump?

 

[morkfromork]

I normally play at 1680 x 1050. I have about £130 to spend plus whatever i can get for my 4850 if i sell it. Not sure what there going for second hand at the moment so would have thought about £200 ish.