Yes you can.Increase gpu 5mhz at a time until you get artifacts,then back it off 10mhz and move on to the memory and increase in the same manner until it gives you trouble like locking up and or artifacts,and back off 10mhz.Then move on to the shaders and increase in the same manner.I've heard the gtx 260's can get up to 700gpu/2250mem/1580 shaders.Goodluck.Try using EVGA new precision utility.It even gives you fan control.
Dahak
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