yeah i get about 18000 marks in 3dmark now 😀 as well I have a 4870 though
but i imagine its either a core is disabled in bios, or its software problems
try booting up w/o as many processes, you can turn off most of the processes in msconfig (type msconfig in the run command on the start menu), but make sure when your done that you remember to turn everything back on... I forgot once and couldn't figure out why i couldn't print my HW 😀