2x512mb ddr2 800 VS 4x512mb ddr2 800

Because I am getting 2x512mb ddr2 800 for now, in the future if i want to upgrade to another 2x512mb
which makes it 4x512mb ddr2 800 equaling a total of 2gb using all 4 slot dimms.

will that decrease in performance? I know about the command rates. 1T and 2T...
using 2 sticks = 1T and using 4 sticks = 2T

but I heard it's not noticeable correct?

Also If using all the 4 dimm slots, will that decrease in overclocking?



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ABIT NF-M2 nView • AMD Opteron 1210 Santa Ana AM2 • NVIDIA GeForce 6600gt (will upgrade)
2GB DDR2 800 Corsair XMS2 • Hitachi 7K160 160GB SATA 3.0gb/s • NEC DVD-RAM • XCLIO 500-Watt