What does Auto & Self refresh rate matter?

I recently ordered a 256 mb stick of Samsung PC2700 DDR memory, from essential computer, and they sent me a different one than the one in the picture

Anyway, I did some research, and the only difference between the one I got and the one I ordered was a differing Auto and Self refresh rate. The one I got has a rate of 15.6us refresh interval(4K/64ms refresh), the one I wanted has a rate of 7.8us refresh interval(8K/64ms refresh). Also, the max frequency of the one I got is 166, the one I wanted is 167, dont know if that matters either. Does the AUto & Self refresh interval matter?

I dont want to waste my time and make a big deal if it doesnt matter, I just wanna get my new computer running.....

Does anyone have any insight on this? Thanks




Heres the links to the data pages:

the ram I wanted:

http://64.4.36.250/cgi-bin/linkrd?_...Unbuffered_DIMM/M368L3223CTL/m368l3223ctl.htm

the ram I got:

http://64.4.36.250/cgi-bin/linkrd?_...Unbuffered_DIMM/M368L3313DTL/m368l3313dtl.htm



Thanks again all.