Current setting is 64MB but I may experiment with a higher setting because in the link posted by spikeychris, there is an iteresting post by coffecup which suggests that there may be a difference of opinion as to what the setting should be.
Will leave thread unresolved for now in case anyone esle has some thoughts on the subject.
Reading abouth this recently, the advice seems to be that if you have a slower card then increasing the AGP may help but it will possible slow down your system. For faster cards the article reckoned it was best to stick at 32 mb. I have tried from 32 to 124 on a mx 440 with 64mb DDR video ram and 512 sdram. Can't say I noticed any difference in performance.
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