Card Saphire 5850 running on 8 x PCI (speeds the same on the x16 no idea why but im happy cos its worth em fitting more now
Overclocked to 900 and fan speed set to 100%
Phonenix: -k poclbm VECTORS BFI_INT AGGRESSION=11
GUIMiner on windows is about the same for me using -v -w128
Overclocking further was only possible (for me) in windows using Trixx and even then only for one card system lost so much stability and used so much more power when going over 900 (because I had to tweek the mV) that I made the call to not bother and stick with a system that requiered less baby sitting.
Soz for spelling mistakes was born that way.
Saw some reports of someone getting near 400MHash and being stable so who knows good luck with your hunt