a question about the precharge operation of hpc ii?

hi ,i have a question ,and please help me

now, i am using the hpcii to control a ddr2 sdram, and there is a selection "auto-precharge" on the megawizard of the hpcii .

if I do not select the "auto-precharge" selection,and i will operate the same row for 100 times (burst length is 4 in full rate), whether the hpcii will issue the precharge command after every burst read or write operation in the 100 times or not ? and whether this kind of operation will influence the cfficiency?

And if I select the "auto-precharge" selection, and I will not assert auto-precharge signal at the first 99 times,and only assert the auto-precharge signal at the last time of the 100 operations ,and whether the operation like that will increase of efficiency ?