Which RAM type to use?

Hey,
I have planned to buy :
Acer Aspire L5100 Athlon 64 X2 4400 2GB, 320GB,DVD-RW,WLAN, VHP

It says : RAM - DDR2 SDRAM

But there are several types of the DDR2, and am confused between:
DDR2 PC5300
DDR2 PC5400
DDR2 PC6400
DDR2 PC8500

Does it matter which one I choose?

Thank you.!!!

 

i wouldn't say it matters to much. but if you really want the best, go with the most expencive