My 1800 has a factory setting of 625mhz/1500mhz but when I go to ATI overdrive in the settings it says requested frequency: 625mhz actual 593mhz, and for mem its requested 749mhz actual 693mhz. The temp is 60*, does the card clock down as it gets hotter? I clicked unlock awhile ago, but am keeping at default setting, unbenounced to me its not keeping its factory timing for some reason..