Asus GTX 580 refrence model temp issue ?

i am running two screens main monitor is using 1920x1080 second monitor is using 2048x1152.
I realize because i am running two screens the card doesn't down clock so idle temps will naturally be higher then normal. my idle temps are 57c with fan speed at 70% when in full load ( bf3) also in fur mark temps get to 74c at 85% fan speed. this is also if i leave the test on for multiple hours or gaming for multiple hours at a time most gaming sessions only get to 70c at 85% fan speed. From looking around it doesn't look like the temps are bad at all but giving that my fan speeds have to be turned up so high to maintain these temps worry me. I have a coolermaster half X chasis so there is plenty of air flow. ambient room temp is usually from 24c - 27c. this is with a ac unit running due to having 3 rigs 2 which run 580's and one which runs a 570 so needless to say quite a bit of heat in the room. Anyways getting off topic does anyone else find these temps to be high with the current fan speeds. would anyone recommend i reseat gpu cooler ? I am looking to sli in new year but agian if this card is running this hot with max fanspeed not to sure how it will fair once a second card is added.

Setup specs
cpu -i72600k
gpu - asus gtx580 refrence model
hd - wd caviar black 1tb , kingston hyperx sata3 (6gb/s) 120gig
psu - Corsair 1200AX
mb - Asus p8p67 evo
chasis - cm half x
monitor's - samsung 27" 1920x1080, Samsung 23" 2048x1152