Unfortunately the 4890 doesn't support eyefinity, that feature was introduced with the 5000 series.
For the uses you have mentioned (eyefinity, gaming) I think the £75 5770 is the best bet.
damn, just compared it on that anand website, 4890 kills it, i had one also

yes i agree, 5770 seems the best option, anymore would be wasting money for him
all of you are top guys, much appreciated
